Most users, however, want the sites and apps they use to remain free AND not have ads.
I think the reality is that most users get very little value out of the web sites and apps they use and would be just as happy to not use them if they disappeared due to low ad revenue. For those that they would actually miss, some large percentage might be willing to pay for them.
In fact, Hulu [1] just announced that they are no longer offering an ad-supported version. That's pretty telling. Either their service was so bad that they couldn't even give it away (doubtful given that they've kept the paid version), or users actually do hate ads and are willing to pay for content that's actually good.
They have a paid version that's a few dollars more without ads, but that's relatively new and still has ads for some shows.
If ad supported free content isn't great, it's at least reasonable - ad supported paid content is absolutely terrible. I think people should categorically reject ad supported paid content or we might end up with another cable tv situation.