In most movies about saving the old theater, school, ball field, etc., the villain is someone who wants to tear down this location to put their own business there, a completely legal and understandable (if somewhat tragic for the protagonists) way to make a living. Often they’re corrupt or try to achieve their goal of obtaining the property through dishonest or illegal means, but sometimes the movie has no other way to paint them as an outright villain than to make them kind of a jerk. (A production intended for kids especially would do this, because the creators think kids are insufficiently intelligent to understand corruption.)
Similarly, landlords (or bankers, etc.) get this treatment simply for demanding that protagonists pay them the money they’re rightfully owed or vacate the premises. If the ‘creditor’ figure is not outright portrayed as a jerk or involved in some underhanded scheme, they still get painted as ‘fabulously wealthy landowner being merciless and unforgiving to characters’ hardships.’
If they have a ‘no pets allowed’ policy it’s usually because they hate animals instead of more legitimate reasons.
The people who think the hero is crazy and needs to be locked up usually think so because the hero is, well … acting totally crazy. In real life, if somebody you know starts going on about voices, special powers, or other worlds, getting mental help for them is generally the right thing to do.
Any time a new boss/authority figure makes any type of budget cuts, it is almost guaranteed that he or she will be portrayed as a villain, and their rising to their position of authority will be portrayed as a Tyrant Takes the Helm moment. Never mind the fact that in Real Life budget cuts are often necessary, particularly in tough economic times. The idea that budget cuts may sometimes be justified is apparently not a popular one with many writers, and all authority figures who suggest budget cuts will be portrayed as an absurdly evil villain who actively hate the arts/their employees/teachers/children/the community and want to cut the budget For the Evulz rather than because of fiscal/economic realities.
In many particularly cheesy kid and teen movies, anyone who doesn’t immediately give the Designated Hero their way is portrayed as a jerkass. A typical example is a character who did nothing worse than compete with the protagonist for something, yet somehow deserves to be punished and humiliated, or a teacher who actually makes the protagonist work and is portrayed as a Sadist Teacher because of it.
This is especially bad when the ‘hero’ belittles, humiliates, and otherwise torments his/her enemy and is portrayed as justified, but when the enemy does the exact same thing, s/he is a jerkass. This often leads to Alternative Character Interpretation: if we only ever see a character’s behavior around someone who hates them, what’s to say they aren’t sweet to their friends and family? This can than make an already Unintentionally Unsympathetic protagonist worse, if they treat their loved ones poorly.
Sitcoms and Telenovelas with a Love Triangle (well, is there any without one?) usually arrange it as a designated couple and ‘the other’, who is an obstacle in the designated couple’s happiness. They are usually referred to as the heroes and villains of the work. However, ‘the other’ may be a villain or not according to what does s/he actually do to keep the relation or in other topics. Specially if the designated couple have just met and ‘the other’ has been in the relation from years ago (and more if there are kids in the scene), doing anything to protect the relation may be perfectly justified in most cases.
In any work based on one’s own experiences, the author will remember someone who caused him or her grief at any given moment through that (understandably) coloured lens, but will not make much effort to give that other party multiple dimensions.