I don't see that any one gigabyte of software I don't want is especially more
     noteworthy than any other gigabyte of software I don't want.

I feel like you're being intentionally naive here. There's a difference between a forum using up a gig here or there, and one of the biggest software makers in the world shipping 4GB to all of its millions of users (if not billions at this point).

> An xBox game can be 50+ gigs.

In my experience a game worth playing never exceeded 1 (one) gig in size.

It is only incompetent creators that feel the need to bury their incompetence under gigabytes of irrelevance.