It comes down to compounding interest. Same as with credit cards or really any similar debt (or investment).
People are: shown the total amount they have to pay to the bank over the life of the loan. It is hundreds of thousands of dollars over 30 years. And most can see in their statement what gets applied to principle and what gets applied to interest.
If they didn't screw themselves and get a loan with early payment penalties they are always free to pay extra anytime they see fit to reduce principle (and if it is early enough it could end up dramatically reducing the total interest paid).
People are: shown the total amount they have to pay to the bank over the life of the loan. It is hundreds of thousands of dollars over 30 years. And most can see in their statement what gets applied to principle and what gets applied to interest.
If they didn't screw themselves and get a loan with early payment penalties they are always free to pay extra anytime they see fit to reduce principle (and if it is early enough it could end up dramatically reducing the total interest paid).
TL;DR: people need to know more math