They can do both, and the two goals reinforce each other -- the skills to do both are pretty non-overlapping anyway. For me, the streaming has been a non-starter so far because I run a MythTV media center and own a Wii -- the only place I can use the streaming right now is on my laptop (a Mac), which is not the best movie viewing machine.
This brings me into the market now, and makes me think that when I move out of my current place (the account is in my roommates name) I'll get my own subscription as well. Assuming I'm not a total outlier (not many people will have MythTV, but there are many people with only a Wii, DVD player, and crappy cable box attached to their TV,) this greatly expands the number of people using streaming, and will thus encourage content producers to see that they need to find a good way to monetize streaming video.
Just because this doesn't benefit you directly and in particular, that doesn't mean its not worthwhile, and in this case a rising tide raises all boats.