Bras do little for us but "look good"

I found out today that the bras do no help with posture or back pain! They are just for looks! I hate bras personally and i always thought people with big boobs had to wear them because of back pain but apparently not. I think its crazy that bras are seen as such a necessity and cost a lot of money. I understand that a sports bra is helpful for sports so that your boobs arent everywhere but other than that its just for looks! It actually makes me so angry!