for b) I would say the contrary. Have you tried entering in a common website from a mobile browser without an adblocker? You get like so many ads, SO MANY, one over the other, some full-screen some that just let you see the 10% of the real site, some with a pseudo-pop-up, all with those little "x" almost unclickable to close them that force you to click on the ad in the end.
And in the "free apps with ads" of the mobile store the situation is even worse... they'll often try all possible tricks to force you to click on the ads.