These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Acceptable Target: The French seem to get made fun of quite a bit, to the point that Darby Conley lampshaded when responding to the backlash over the Pittsburgh joke, citing France is among many other places that are acceptable to make fun of.
Dude, Not Funny!: The joke about Pittsburgh didn't really sit well with the residents of Pittsburgh.
In a 2005 strip, Bucky whacks Satchel in the back of the head with a TV remote so hard it causes him to cry, all over a piece of cheese. Although Satchel is often the victim of Bucky's brutality, and Bucky has made Satchel cry before (and over insignificant things), many, many fans felt this was an absolute low point for the comic.
Ensemble Darkhorse: Mac Manc Mcmanx is a pretty darn cool and funny character. He speaks in all sorts of brit lingo and apparently squats in Rob's house.
It certainly doesn't hurt matters that he's not a Jerk Ass like Bucky is.
Hilarious in Hindsight: Bucky doctored one of Satchel's Where's Waldo? books by changing it to Where's Osama?. At the end, a bunch of American troops find him, and presumably kill him, prompting Rob to say "you can't sell this to kids". In 2011...
Misaimed Fandom: PETA fans don't seem to realize that the strip doesn't exactly cheer for the organization.
Padding: The newer strips tend to draw their jokes out to ridiculous lengths, often to the point where it's same subject several weeks later and has pretty much devolved into rephrasing the same punchline as many times as possible.
The Woobie: Satchel, who is almost always being abused by Bucky, both verbally and physically.
Also Bucky's cousin Mac Manc Mcmanx counts. His girlfriend got in a huge fight with him, he got a teacup/plate embedded in his skull, he was detained by airport security and mistaken as a terrorist, no one can understand his dialect except Bucky and above all, he's an Ugly Cute. Awww......someone give him a hug already!