Why did Augustus May Who and his classmates tease the Grinch with having a beard if the Grinch didn't have one? Yeah, he had more hair than the other Whos, but there was no noticeable beard or anything that looked similar to it.
Because kids can be dicks or, as we say on Tvtropes, Children Are Cruel. Bullies, in general, don't care about how true the insults they dole out are; they just dole them out to hurt the bullied, pouncing on any unique feature the bullied so happen to have. In this case, the Grinch is hairier than the other kids, so, the extra hair he does have would be mocked as a beard, when it was probably more like fur or fuzz.
Why didn't they seek him out? Didn't they love him?
If the Who sisters who raised the Grinch or Martha May Whovier missed him so much, why did none of them think of going to Mount Culprit and speaking with him to convince him to return - or, at the very least, to keep in touch with him? All Whos know that the Grinch lives in Mount Culprit. Yes, the Grinch was antisocial, but surely he would have wanted to hear what his adoptive mothers and his school crush wanted to say to him.
Here's another question to tie into that: why didn't they stand up for him at all when he was being teased? Considering that Martha was way nicer than Augustus and all the other classmates, she could've easily told them off for that.
To answer the first one, they probably tried to but he never answered them back and, so, they probably stopped reaching out. For the second one about Martha, she was a kid, too, and, while she couldn't stand it, she probably couldn't do a lot to stand up for him directly but she could be as nice as she was toward him to offset some of their bullying.
From what I got, the Whos mostly go with the group and the status quo, which probably answers why no one stood up for him, went looking for him, or why the Whos do a lot of what they do.
The Grinch's Back Story about the origins of his hatred towards Christmas doesn't make too much sense if examined closely. He proclaimed his hatred of Christmas because all his class minus Martha May Whovier mocked him for cutting his face while trying to shave. However, that's it. He only shaved because of Augustus May Who claims that he had a beard and to look his best to make an impression towards Martha, given that he wanted to give her a makeshift angel he made for her. Because he deeply loved her. Christmas had nothing to do with his failed attempt to shave. It would have been different if maybe Augustus mocked him for having a beard like that of Santa Claus, but he didn't. Thus, rather than yelling "Stupid present! Stupid tree!! I HATE Christmas!!!", the Grinch should have yelled instead "Stupid Augustus! Stupid class!! I HATE bullying!!!"?
He was bullied even worse around and during Christmas celebrations and, adding to this, he was an eight year old acting the spur of the moment.
The start of his hatred towards Christmas does make (more) sense from a child psych standpoint, as kids can react strongly to negative events, especially if there's an association with an overarching event, and, sometimes, they can have a hard time moving past a bad experience. For the Grinch, that event was one in a long list in a line of bad experiences with the holidays, so he probably grew to dislike them overtime before that point, though, besides Christmas, remember, he seems to hate the Whos and Who society in general.
Whe use of the clippers/razor
Why was there a razor at the Grinch's house? The only two other residents were his adoptive mothers and the Grinch was still too young to have a beard he could shave. With that in mind, why didn't the Grinch think to ask them for assistance in shaving his face correctly?
Actually, those were clippers. Why he didn't ask his moms? Well, maybe he didn't think they'd know how or he did it in secret (and didn't want to get in trouble).
The Grinch has fur all over his body. And apparently he sheds. The clippers were likely used to keep his body trimmed and his guardians likely did the work.
Bribing the Judges?
In the Deleted Scene in which the lighting contest between Betty Lou Who and Martha May Whovier is held, Betty wins the contest by displaying the amazing lights of her house, and the judges deliver a paper with her name written on it to the Mayor so he can announce the winner. Of course, being the corrupt Jerkass he is, Augustus plays favorites and declares Martha as the winner under the pretext that it was a split decision, as he plans to propose to her later on, leaving Betty saddened for losing to Martha yet again. However, the judges wrote Betty's name on the paper, so why didn’t they protest or berate Augustus for naming Martha the winner when they had already decided that Betty had won?
Well, the mayor was a bully when he was a kid, so, maybe, as a mayor, he's a bully to the citizens, too. I mean, from what it looks like, that Christmas was probably the first time anyone's really ever stood up to the Mayor.
The novelization explains why: Who Bris (the mayor's assistant) ushers the confused judges away before they can say anything and stuffs money into their pockets to keep them quiet.
Why they don't just toss dude in jail?
If the Grinch often terrorized Whoville with his pranks, why did the police never try to arrest him? The Mayor would surely have loved to get rid of him, and as far as we see, the Grinch's visits to Whoville endangered people, like when he gives two girls a hacksaw or when he causes all that mess during the Cheermeister Celebration. If all of Whoville knew that the Grinch lived at Mount Culprit, why didn't the police arrest him for child endangerment and causing a public disturbance?
Because he's always in disguise when he pulls those pranks. Even when people see him, he's wearing a mask.
The Grinch is also superhumanly strong/athletic and a Gadgateer Genius. It's probable Whoville's police force simply stands no chance against him.
Growing in her their noses?
While the Whos have strange faces and noses, the Who children from the Grinch's flashback, including Martha and Augustus, and Cindy Lou in the present, have normal human faces and noses. Why the difference?
Probable real-life answer: to save time and money, since putting that makeup on takes hours. If those poor kids don't have to wear it, let's not make them. Possible in-universe answer: perhaps the faces and noses don't appear until they go through a kind of Who puberty, and they're all still too young? And for what it's worth, Cindy didn't have those features in the animated special, either. Might be an homage.
At one point in the movie, the Mayor says "grown into her nose yet", so the latter seems to be confirmed.
Another question, Martha could easily pass as a human in our world. Why does she have a fully human-like face even though she's an adult, other than the fact that it makes her more attractive and less weird-looking than the other Whos?
Prolly a Goodness Equals Beauty thing. She does have a Who facial structure but it's less obvious but, in comparison to the Mayor (who is, IMO, rather pug-faced), she's more human because, well, she displays humanity in a sense.
Grinch's heart is too small?
Just like the book, the narration near the opening of the film states the most likely reason the Grinch hates Christmas is because his heart was two sizes too small. After the Grinch comes come from causing mayhem in Whoville, he measures his heart and it's now down a size-and-a-half, meaning it is three-and-a-half sizes too small. At the end of the film after his heart grows three sizes, which would still make his heart half a size too small to love Christmas by that math.
It's mostly a joke to justify why the Grinch is still an acerbic Deadpan Snarker at the end of the film. He's goot, but not too good, so his heart is close enough to the size required to love Christmas but let's not get carried away.
