Why don't more intelligent people realize that the whole expensive engagement ring tradition stupid and ostentatious? I understand the value in signaling to others that you're married, but no need to spend more than 20$ to do that.

My parents went with simple silver (colored?) bands. I'll do the same or just nothing at all. My girlfriend couldn't care less about a ring and doesn't want a formal wedding either... I'd have a hard time being with anyone who felt the need to constantly show off their status with a shiny rock on their hand.