Please be friendly to each other, it's all we've got.
I've been in this town a long time I say hi to people in my neighborhood. When i see you walking your dog and say something pleasant and you look down. it's not weird for me. but I imagine it would be for you because we're neighbors and see each other constantly. Also if you look like a hispter pediophile and make eye contact without smiling or acknowledging another's existence I will ALWAYS laugh my ass off and the one time that man boy asked what was funny I fully explained myself. Or that time the kid didn't hold the door to the max as i was running my ass off downtown. he didn't expect me to beat it to the next stop and sure as shit didn't expect the scolding lesson I gave him.
So Just be nice don't try to look cool by not smiling, you just look like a dick. if you want to live in a city where you don't have to care about other people move to fucking NYC