Seriously, the only time I look at avatars are on the CAG forum, and that's because people's "MyGamerCard" is in their signature. I rarely look at the real friends list in the dashboard that has people's avatars on it, because I normally go to the Xbox Guide and view my Friends list from there, and it's just like the past friends list.
I don't mind dressing my guy, but depending on what it is, 100 isn't 'that' bad. That's less than $2 for something I would probably only buy once in my lifetime. If I felt cheap, I would just ask my friends if I could borrow $.25, and before I knew it, I could scavenge up $2. Now I know that's not the point because Microsoft is still charging 100, but I still don't mind. If it's anything more than 100, then that's pretty ridiculous.