why can i not find a 500gb ps3?

I'll be honest, I'd love to find a gta bundle 500gb but those are gone. The only bundles comes with 250gb. Why can't I find a 500gb ps3?

I was just looking for one yesterday on Amazon and only found the core system 500gb unit for sale, at almost $100 more than the 250gb bundle with game. I'd have to go with the cheaper in this case if I do decide to buy a PS3. 250gb is plenty for what I would be using it for, considering I have the PS4 for other stuff. Maybe it was just a promotional thing and they all sold out?