When meeting people for the first time, I will often say something quirky just as test. Their reaction is great info to have. There are so many different reactions that a rude response is a major red flag and I'm done or wary from then on.

Good responses are, on one side of spectrum, they think it's funny and interesting. In the middle (also good responses) they or ask why or politely disagree. On the not so good, they politely disagree but think you're stupid without saying it. Then, out of all those response options, if they pick being rude, then you have a very strong indicator.