Online ads are not uniquely malicious, although they are more pervasive (even reading a magazine, the page I am actively reading will not have an ad in between paragraphs, though the next page might). I do think modern marketing firms (and often therefore web) have developed more effective -- and therefore bad -- techniques to have the effect they are paid for.

PS. I upvoted you because I don't think it was a bad question. If I had to guess, it may be misconstrued as a [bad] rhetorical question arguing that "you already have to put up with X, so it's pointless/inconsistent/illogical to reduce your exposure to X".