I'm not wired for retail. I find gallery-sitting exhausting but it's part of the deal at our local gallery. My fellow exhibitors and I split the responsibilities for chitchatting with art lovers and looky-lous.
"I've never seen anything like that before." Is that a compliment? Don't ask them to explain. Don't say what do you mean? Just say thank you. And change the subject, maybe to where they are going to eat lunch.
Some people bring their children, some people bring their dogs. Some people buy stuff, which makes us all happy because it's validation: We made something out of nothing that someone wants enough to buy and bring home with them. Hooray! Now I'll make some more.