XKCD, Oglaf and other webcomics have title text on mouseover (perhaps because that’s the easiest implementation, not even requiring CSS or JS) but this does not work well on mobile (at best, long press reveals some of the title text), which is why some implement the clicking.

Also, the red button is in an obvious spot in landscape mode but too far down for most mobile users to scroll (and they might think it’s some kind of promo).