The content companies do believe they are God's gift to mankind and they have some very anti-customer policies. They think they are optimizing their revenue from such policies.
I think they underestimate the kind of growth they could see if they started treating their customers the way that most of the tech industry does.
Tech is far from perfect, but it does a better job of being customer centric.
There are certainly ways that tech companies operate in a Hollywoodesque manner.
Apple trying to assert DMCA against jailbreaking phones is a great example. It's YOUR phone. You paid $600 for it (either over time, or up front). You should be able to do whatever you want with it.
You've made a very poor case with Google privacy policies, though. If you don't use Google+, there's no way for any of its privacy policies to affect you. If you don't like their policies, don't use their free product. Period.
In essence, my argument is this: because at their core, they are an unbiased source of information, the less controlling interests involved, the better.
To generate revenue from ads is to "sell" a piece of themselves. Equate it somewhat to raising money from investors. They now have much more revenue, but at the cost of some of the control of their company. Ads certainly don't take away control in the sense investors do, but depending on the revenue from ads in any way is an extremely slippery slope.
How about only showing the ads until each month's (or the year's) costs are met?
That way there's no temptation to try to derive a profit from it, and at worst you end up with ads on Wikipedia for a couple of months out of the year (kind of like you get now).