Things that people say that immediately alienate and annoy me:
"I'm not really a 'cake person'."
"I love dolphins!"
"When it's fantasy football season..." (this one is so alienating that I check out before the sentence is finished)
"Do you and your husband go running together?"
Things I say that alienate and annoy others:
"I don't ride bikes."
"I hate horses."
"Hemmingway makes me want to slit my wrists."
"I don't like reading non-fiction. I makes me want to take a nap."
"I hate camping."