I thought like this, too, until I realized it was crazy to restrict myself based on a camera I might get in a few years. I bought my 10-22 used (read: you will be able to sell it if you go FF) and I am happy with it. I rarely use it wider than around f/8. Unlike some, I do use the full focal length range.
Same here. I waffled around for months because the EF-S scared me off, until I realized it'd be years before I'd ever get a full frame, if then. I bought it and haven't regretted it a moment. Plus, as has been said, it holds its value as well or better than any other EF-S on the market.
Incidentally, it makes a surprisingly good portrait lens at 22mm. I'd never have thought that, but my wife put it on her 50D and shot lights out on some bridal portraits a few weeks back. Gorgeous results.