+1 In any major city it's probably 90% chance they're either a crook trying to scam you out of something or mentally not quite right. The remaining 10% will be tourists or people from outside of the major city.
Nobody wants randos coming up to them and asking for something.
Most people would be less lonely if everyone had more practice at making non-transactional conversation.
Actively avoiding conversation still qualifies as "weirdo" behavior to most people.
Are you willfully ignoring people at bars, night clubs, supermarkets, etc?
It's obvious 99% of the time whether or not the conversation is in the wrong place and wrong time.
Supermarkets are a toss up. Most people are there to get their food and get out.
Scamming crools frequently do have good social skills, but of course there is that risk of being scammed if you talk to them.