Frankly I find it flattering when people asked me certain kinds of questions!

Maybe I’m just more generous with my time than others (or perhaps I don’t value it), but all these responses saying friends and colleagues asking you questions they could’ve theoretically looked up are “wasting your time” are rather perplexing. If somebody’s asking me, like you said, I generally assume they have a reason for asking. Or maybe they’re just tired and don’t want to spend an hour looking it up and verifying it because they know I have a quick answer that takes me little to no effort. I don’t see anything wrong with that. I get asked camera questions all the time, and frankly I just see those as opportunities to stay sharp. No better way to learn/reinforce your knowledge than teaching others