I think everyone thinks I'm a vegan but I eat meat sometimes
Why don't you tell them you're not vegan?
They always try to be so nice to me, and think I'm saving animals when I'm not.
Having people be nice to you is really a lot of fun, but you have that for reasons that are not true. Explain to them all that you do eat meat at times, because one day when they see you eating it they will be shocked and angered at you.
I hate vegans, so I'm in.
You shouldn't hate anyone just based on their diet!  That's pretty closeminded of you!