Oh, so thats why he left…

Why? I'm so oblivious

cause he might have become a hybrid, he has ears in last panel

Yes, i think so too. I think he put up a kind face and understanding personality as facade, but deep inside he felt slight disgust - just like most ppl when they give things to homeless ppl… they are happy to give, but not everything… then he felt remorse as he became one of them…
I think