You can certainly be forgiven if you stopped reading the article at that sentence, because that is a frequently-beaten dead horse.
However, Atwood is actually making the exact opposite point: he goes on to say that people are justified to gripe about $3.99 apps because the quality of apps is so uneven and there's no real way to ascertain the quality of an app before you buy it.
He says we'd certainly be justified about complaining about $3.99 cups of coffee, too, if only 1 in 5 $3.99 cups of coffee was actually a decent cup of coffee!
Every single time there is a post like this we beat the same dead horse.