because crap is cheap to make, and a certain percentage of the crap is going to sell enough to make up for the losses from the rest.
The problem is that crap isn't that cheap to make unless it's absolute crap. Most of the big-budget crap could be considered mediocre but in such a saturated market, mediocre doesn't cut it. As the article said, publishers should be focusing on making better games with lower budgets. In other words, less focus on presentation, more focus on gameplay.