Yup, a lot of places do this. Oh I can just get a large popcorn for 50 cents more. I'm already paying 5 bucks so whats the difference.
The best value to me seems to be the 30 day rental (for the one you showed). That's enough time to play the game without really being stressed. 4 hours is just stupid and why I feel like they should just offer a limited amount of free time like half hour or an hour or something.
PS Now is not a demo service though.
Say for example they offer Journey on PS Now. That game could be beaten in 2 hours, so a 4 hour rental would be enough to actually beat the game. Infamous Second Son if rushed through can be beaten in 8-10 hours. A 4 hour rental just god you midway through the game.
I'm sure the 4 hour thing was meant as a way to actually play the full game for cheap for a long enough period to get a good feel for exactly what the product has to offer. I mean if I sat back and played a game like Divinity for 4 hours, I would experience .01% of the game but would still have a general feel for how the rest of the game would be, and would give me enough time to get addicted to the product and want more.
Thats about all it is for. Get a small taste, see if you will actually like it or not, and then give you the option to purchase the game or rent it for a week or whatever.
I mean it is all choice here. I have yet to see a game with the only option being 4 hours lol, so harping on that single price point when the others are just fine is a little crazy. $5.99 for 7 days is the money shot for me. Perfect price, but indeed it is all about the game too so sometimes that 7 days is $3.99 or $6.99.