Yes, Banks wont really make you rich nor make your money doubled. The only purpose of bank is to secure your money so basically, your money won't move. It will just stay to the bank until you pulled it out. Better go on investment.
The purpose of the banks is to only enrich themselves and they do it by using the funds that their customers have invested or saved at their banks. If you look at the interest they add to the accounts of the of its customers its teally ridiculous.