Obviously speculation, it's either pride or the lazyness of trying to figure out the most comfortable way for the user to deal with it.

I mean Lord Gaben quote is famous for a reason:

Ninety percent of games lose money; 10 percent make a lot of money. And theres a consistency around the competitive advantages you create, so if you can actually learn how to do the art, the design, and the programming, you would be consistently very profitable.

So to succeed (and not get frustrated with the user-base) the developer has to make things convenient for the user, when this isn't possible the developer give the valid reason of why not (thus forwarding the frustrations of the users to Valve).

Note: Hindsight sure is a beautiful thing.