Or it's curiosity (genuine or polite). Maybe, for some people it tips the scale into trying the app either because they were already thinking about trying some/any app, or switching away from their current one.

I don't know if anyone who's asked me has started using the app as a result, but I think it (anecdotally, again) supports an idea that a successful results for one app organically helps its name recognition.

Edit: unless you meant the difference was between people asking which app vs which spouse.