Yeah, I guess I was thinking they might throw a lot of money behind it short term to get enough content on there to be compelling without a per-title-payment option, and let it snowball to a point where it can attract content on its own without subsidy. I didn't think it would necessarily have to have 'all the games', or that it would necessarily compete with the other platforms to have all multiplat games, but to have just enough to be an interesting offering.
But even if the service isn't purely an all-in-one sub, I would expect there should be that aspect to it. I presume there's going to be some kind of fee to access the service aside from per-title payments*, and for that, I guess there should be 'some' content included.
* I'm doubting Google will let you play a game indefinitely on the service for a one-time payment, without some kind of access sub, but I guess they might do that if they think it's sustainable. The other possibility other than an access fee is if Google tries what Sony did initially with Now, and abandoned - time-based per title rentals. That avoids the need for an additional flat access fee, but it has its own appeal problems of course. The exact business model will be interesting to watch anyway... they have an opportunity to start from scratch here, without any of the legacy headaches some others have to deal with.