YARN!!!!!

Ugh,
I can't believe how expensive yarn is! I love knitting but yarn is soooo damn expensive. Okay, well, yes, I have nice taste and I could settle for lesser quality but what's the point of spending hours on something if it's going to be scratchy and yucky?
I told Solomon that I would knit him a sweater next. I'm looking for a cute cotton, stripe design, so I could do pink and blue stripes (his favorite colors). I got some books from the library and I love the patterns. Easy, fast and cute. Yarn Girls is the name. So I was looking at the website online, www.theyarnco.com and they have Yarn Girl kits you can buy, pattern (they will customly size it for you, so I could do matching sweaters for the kids!) and the yarn to make it, perfect. Just what I need since I rarely have time to go to a yarn shop and look around. But then I'm looking at the price of making a kid's sweater, ack! We're talking $60-$100 for a little boy's cotton sweater! What's the deal? So far I haven't made anything that required very many skeins of yarn. The sweater (yes I'm still working on it) for Margo that is wool/bamboo blend cost $8 a skein and I had to buy 4 but it didn't seem unreasonable but we're talking like 8 to make a sweater for Solomon and then it's suddenly twice as expensive and just seems a little rediculous for a kid. Especially since I'm thinking of a sweater for Summer nights, etc... i.e. not a fancy dress sweater, a kick around sweater! I don't spend $60-100 on sweaters for me and not ones that I still would have to put hours of work into making!
I'm not so sure about my new hobby, but it's too late now I'm an addict and apparently a yarn snob to boot.
What's a girl to do?