Similar to some of the guys here, I'm strictly a leisure traveler out of my own pocket (no chance for business travel in my current company).
I feel SPG is pretty balanced compared to other programs in terms of loyalty benefits and hotel footprint. I'm still single (though am currently looking) so I guess traveling is something I can do while I still can.
I also travel to destinations with some SPG presence. However, cheap air tickets and cheap to moderate hotel costs are still the deciding factor to where I go for trips and to pass my time.