Huh? 99% of domains point to some nameserver they aren't contracting service? That is, 99% have invalid NS? (Obviously when I say somebody else's NS I mean a N

Huh? 99% of domains point to some nameserver they aren't contracting service? That is, 99% have invalid NS? (Obviously when I say somebody else's NS I mean a NS they have zero reason to think would respond with correct records. Obviously not talking about outsourcing DNS hosting.)