Nobody likes getting trolled on their answers. You can understand it more if you ask a question, but when you are trying to give advice, having somebody make rude remarks is just annoying. I like it because it encourages people to answer questions.
That would just make it easier for people to troll/hate, and we couldn't simply block them because they're anonymous. Plus, it would be hard to tell who is saying what is more than one anonymous person comments on an answer. I think it's fine the way it is.
great question. I'm sure that'll be the next feature they add to this site
Anonymous comments would just make for even more trolling. There's no real need to be anonymous to comment imo. Just too much logistics. You wouldn't be able to tell anonymous commenters from one another either...