If certain games require it, then it is something forced by those games, not by the service itself.
Just as those "off the shelf" games that are account tied, as Diablo 3 or Starcraft 2, it does not imply that all physical games are account tied.
An exception does not a rule make, while in the case of Microsoft that would have been "the rule".
So you don't buy games that require XBox One?
You had a choice before. Now that choice has been removed.