It's true that it's a minor irritation, and definitely nothing compared to the assault we get from TV and the web. It's just not what I'm used to when I curl up with a book. (except for certain paperbacks from the 70s with glossy cigarrette ad inserts in the middle! Remember those?) I want the option of maintaining the sense of stillness and solidity that I get when I read a physical book, not be reminded of the ever-shifting and invasive social-soliciting web.
I would have easily learned to tolerate it, if I hadn't found out that I didn't have to. Think about any new advertising encroachment, e.g. on the toilet stall door opposite the shitter, and how intolerable it would suddenly seem if an easy few steps would reverse that encroachment. That is, if you're really bothered by advertising. (Which I don't recommend, if you have a choice about it)