While it is true that you never outright said that the create-a-quest feature was going to be implemented, there's still the technical lie by omission. The original JP version of the game had the quest creator, and all the online preview sites were talking about it being one of the new features of the game as a whole, so of course everyone is going to assume we'd get the game just like the original JP version of the release. There was plenty of hype for the game and a lot of people would obviously have known about the quest creation in the JP release, so there's really no excuse to have not nipped this problem in the bud and told people BEFORE releasing it that the creator was cut (instead of having to find out post-release).
I'm happy I bought the game as it supports you guys, but I find it very disappointing that Atlus US decided to handle the announcement of the cut in such a half-hearted and shady way especially when you tend to avoid such tricks for any of your other games. Atlus is one of my favorite companies, so I'd hate for the company to start having a trend of not letting people know about altered content until after release.