This is a beautiful quote because it is an example of one industry's bad behavior leading to another industry's bad behavior, upon which the first industry then users the second's similarity to justify themselves. Cars only started doing this because phones made it normal. It's wrong in both cases.
It's similar to when Apple defended it's 30% store cut by claiming it's an "industry standard"... specifically, an industry standard that Apple established.
Steam also don't engage in anti-competitive behavior and prevent billions of people from using alternative game distribution methods like Apple does.
What we need is real competition in the mobile app distribution market to determine whether or not that 30% is actually fair, efficient and competitive. As it stands, there is no competition in mobile app distribution.
What percentage of that transaction do you think Best Buy would take?