Yes, I'd agree that it's been common to "skip a version" or similar. Effectively you get Photoshop (or whatever) at a reduced cost.

So you can see the logic behind Creative Cloud: Adobe have both prevented this behaviour, and struck against piracy. They're clearly betting that this will outweigh the reduced sales, and that Photoshop/Illustrator/InDesign are so essential that few people will pass it up. I'm not convinced they're right.