I have over 60 apps on my wishlist. If I bought them all, it'd easily be $500 because there's the $0.99 apps, the $2.99 ones, and then the $20-50 ones.
I put them there so I can find them again and see if I really am still interested in them. Why invest into a bunch of $0.99 apps when you can get the biggest bang for your buck with the $49.99 one?
The problem with free apps is that they just take up space in your purchase history and you have to deal with hiding them just so your list doesn't take ages to load. So you don't want to download them all, just because of the hassle later on. I have over 2,000 on mine since I've been downloading apps since the store opened.