Furry Fandom, how do you madden me? Let me count the ways.
1. The amount of entitled people who think that just because people in the fandom know how to draw, they should draw them and for free.
Latest example of this I have seen? Someone asking for a 24 minute-long animation for free and getting offended when people told them they might want to consider saving up a budget.
> See also: begging for art, requesting when no requests are being offered and price-wanking when fandom-prices are already insultingly cheap in most cases.
2. Lack of respect for people's personal boundaries.
Just because someone drew a pin-up doesn't mean you get to state how many loads you blew while looking at the picture. "This looks very sexy." is OK. "OH MURR I CAME" is not and I hate the fact that for some people it just won't sink in that this is not acceptable behaviour, especially when people go out of their way to mention in the image-description that creepy comments are not welcome.
3. Tied to point 2: the fetishes, some of them being pretty damn disturbing. You are free to like what you like, draw what you like and fav what you like.
But don't take what you like and start shoving it down people's throats because you will be seen (and then shunned) for being "that guy/girl/..it". Also, don't identify yourself on the forums as "That person who likes wearing diapers and is really into porn, porn and more porn" (just an example). You wouldn't introduce yourself like that in real life, why the hell would you do this online?
There are more things, but these are the three things that tend to rub me the wrong way the most.