Why is it that adults now deliver newspapers?

I personally was far too pampered to deliver newspapers as a kid, but many other people I know (like my wife Jeannette) did deliver newspapers growing up. Anecdotally, at least, newspaper deliverers are now mostly adults with cars, rather than kids on bikes.

Does anyone have any theories as to why? I can think of many possible explanations, but none of them ring true to me. One hypothesis is that it paid much worse 30 years ago relative to other jobs, so adults wouldn’t do it, only kids. I doubt that is true though. Is it that kids aren’t willing to get up early in the morning anymore? Or, maybe kids mostly do still deliver, but I don’t know many teenagers so I just don’t hear about it?

Maybe blog readers have better answers.