Nightgame: usually takes place at some social function like a party or a bar. People are going to be in the vicinity for a while, so you can go over and talk to them now or later or whenever. If you say something boring, you'll have another chance later. And people are expecting to be social.

Daygame: can take place in a store (IE:Target), or a park, or a fast food restaurant. People are on the move, so you're only going to get one quick chance to say something, and it better be good, or she's gone. And people aren't really looking to be social.

Is that a good description?

And if so, daygame is obviously more difficult than nightgame?