My dentures have thin spots on gums. Looks too thin to last. Is this normal for full dentures or a sign of an inferior product?

New full set of hard permanent dentures. So thin you can see thru them in several places on the side gums and roof of mouth. Can see the ends of a few teeth from inside top plate. Looks too thin to last for several years. I'm on a limited income and cannot afford to replace them every few years.