They arent “doing it”, that’s just how debt is amortized over a set period if you want fixed payments. Otherwise payments would be really large in the beginnin

They arent “doing it”, that’s just how debt is amortized over a set period if you want fixed payments. Otherwise payments would be really large in the beginning and decrease over time as the remaining debt get smaller and smaller. If you want to pay more principle, either increase your down payment or get a shorter amortization period.