Can advertisers PROVE younger viewers are better targets?

"Young viewers are better" goes the common wisdom amongst advertisers.
They say younger people have more money (since when?... most I've met
are barely above minimum wage & in severe debt), are not brand-loyal,
and therefore tv shows should target the young 15-25 or 18-35
demographics.

So where's the proof?

The reason I ask is because AARP/Roper/ASW have produced a study
that 50+ persons are the TRUE market since they have tons of money,
high-paying jobs, virtually no debt, and little brand-loyalty. Some
have debunked this study as "biased". Okay fine.

Where are the studies proving that the 15-35 market is
better/preferable to the 50+ crowd? I'd like to see them please.

Deke...

ravenlynne...

I'd like to see the categories changed anyway. being 30 I neither know
or have anything in common with most 18 year olds and i'm fairly
certain I don't watch the same shows...

Very simple answer. Older viewers (like myself) can afford to buy a DVR or
three, and skip the frigging commercials.
That and the fact that the younger crowd are generally
1. more impresionable
2. have fewer large bills (mortgage)
3. are less cynical of advertising
4. have to have the latest thing to be "cool"
From what I can gather, the study has some major flaws in it.