I've been thinking back to the relationship that I was in when I was 18 - 22 or so. We never really went on many "dates." We didn't have that much money, but we weren't dirt-poor or anything. Movies, occassionally. Lived in a small town, but that's just an excuse.
When I look back on it, it was really just that we didn't have common interests. We finally broke up (one of the smartest things I've ever done; the stupidest was date the same person all the way through college).
When I met my wife, though, it was just completely different. What I liked to do, she liked to do. New things that I found I enjoyed, she tended to as well (and vice versa). There are some exceptions, but we'd find ourselves wanting to see the same movies, go to the same stores, go to different restaurants and try new foods, do the artsy stuff, the museums and plays and concerts and all of that.
Without wanting to be a downer, it kinda seems to me that finding something to do together SHOULDN'T be a problem, if you're inherently compatible.