Sometimes there really is a better way to solve their problem. Sometimes, the problem they have can be guessed reasonably accurately, and solving it for them is useful. I've found such answers helpful in the past.

I've replied to "does anyone know where the nearest ATM is?" with "the pub we're going to has no card transaction fees or minimum spend". It doesn't necessarily solve their problem, but there's enough chance that it does, that I feel it's a useful thing to say.