I don't. I too have bought all the DLC, so I wouldn't be getting any choices for "free". Old content is old.
There are players who have no interest in playing DAO, DAA, or DA2, but might be aware of what some of the options are and want to make choices without playing those games. I've seen many DAO fans who have no interest at all in playing DA2, or stopped playing DA2 and won't pick it up again. There are DA2 fans that dislike DAO and find it tedious. There are DAO players who never bought the DAA expansion; they might dislike expansions, or had no interest in playing it since their Warden was dead (despite the unfortunate import decision/error allowing such a play).
I highly doubt they will restrict selection of options in the Keep based on the products associated with your account. They want new players to be able to use it as well, not only with DAI but with future games. As the franchise gets larger with more games added, the likelihood the players will have played the early games decreases.
agreed, to restrict choices based on content the player owns would be petty, there is also the issue of people who don't register their content, I know people with both games and all the dlc who haven't registered their stuff, they play off line, the ony time they go online is to download dlcs and updates.