This is also effectively true for the more broadly used Google Adsense (not just DFP). They do support displaying adsense, but then screen out all non-https ads. Which, of course, results in a lower CPM.[1]
Depends on what the bills are for. Most sites that don't have content-production staff need twenty bucks a month for hosting, plus an occasional prod from a sysadmin.
Are there some types of content where the author, photographer, etc will produce it without direct compensation? Sure.
Are there others where that's not practical? Also, yes. Maybe not things that you need, but this problem does exist.
At the moment, there's not a model, outside of ads, that works very well for that sort of thing. There are some subscription/micropayment schemes that seem promising, but nothing that works as well as ads do.
I didn't say it was supposed to work for all sites, just that st3v3r is ignoring a huge swath of the internet by implying that nonprofessional sites don't exist.
[1]https://support.google.com/adsense/answer/10528?hl=en
>>In short; Google will penalize me because I use Google
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