Themes and Gamer Pictures - To Buy or Not To Buy?

I have been playing on the Xbox 360 for just a few months now (traded in my Playstation 2 for one when it died back in February or March - I forget which), and I find that I don't Generally spend many points on Themes and Gamer Pictures. I got the Viva Piñata Gamer Pictures and Theme for my wife and son (never really got into that game much myself), got one of the Lego Star Wars picture packs for my son (who promptly decided that he didn't want to use any of them anyway, so that was a waste of points), and I did pick up one of the Brothers in Arms: Hell's Highway picture packs for my current gamer picture (even though I haven't - and probably won't - ever played that game). My current dashboard theme is the default one, even with all the others to choose from. I download all the free gamer pictures and themes that become available on the marketplace, even if nobody around here ever uses them... I don't know why; I just do. I download all the freebies on the marketplace, even if I don't have the game it's for...

So, what about you? Do you buy gamer pictures and themes? If so, do you actually use them?