[treis]

The origin of banks are people with castles agreeing to store valuables of people that don't have castles. You pay them to do that so you don't get robbed and lose your money.

So if you take your max int loan, where are you going to put it? Anywhere you store it has risk. Cash under the mattress can get robbed and investments can go bad.

If you really really want to be sure you get your money back then banks are the only option and in this case it's worth it to pay them.