You don't have any qualms about spending $300 on a sport coat, but $10 milk is highway robbery. And while your $200 jeans were considered a fine investment, $7 toothpaste won't fly. It's understandable, you'd rather put your money towards stuff you really like, but as a result, your perception of what a "necessity" is has been totally messed up.
6. You get sticker shock at everything that isn't clothing.