Look, if I am challenged to a game of horny chicken in public by a stranger then I am bound by oath to accept.

yea, just because they call you it doesn't make it true, if it seems someone is talking to you, it isn't awkward to reply to it but, if someone was talking to you and you ignore them, it just makes an already awkward situation more awkward. It's much better to then respond to the person, then once realized it wasn't to you, saying "oh I thought you were talking to me" and lightly laugh to indicate that it was in good faith/you took no offense/that it was a silly mistake.

By not responding at all, if it turned out they /were/ talking to you, you are ignoring them, then when you do find out they were talking to you it would be even more awkward than if you just responded normally, and whats worse from that is, it would be awkwardness that you created by not replying instead of it being awkwardness that the other person created by calling you a thirsty little boy.

In this case it would have worked out, since they wern't talking to you in the first place, but... if they were talking to you then it would be hella awk ignoring them. And that's ignoring that they'll almost certainly try to address you again louder and potentially drawing more attention onto the situation.

I don't know, maybe I'm just looking way too far into it but, that's my thought process.