Hm. Provided I know the person well enough, I have little problem bursting their bubble is the thing seems impractical or impossible. For example, my mother has this very expensive house that she wants. She sees "great house". I see "house we have to clean" and "very expensive bills". This said, I haven't seen the inside of the house .To me, the situation is very impractical, and seriously, where are we gonna get that kind of money? In another situation: I love music and writing. Given the chance, I'd do them the rest of my life. However, I know how much money they don't make, usually. Therefore, it's a dream, and I really wish it could come true, but I don't see how. Right now, I'm looking for something that will support my habit, as I don't see my habit supporting me (save a miniscule chance, which I'm not hoping for).

In short, I think there's nothing wrong with realism.