I do because it serves the lowest common denominator, anybody can pick up and play Call of Duty and get somewhere in it.
However, not anybody can pick up a game like Demon's Souls and make progress without pain and sacrifice.
Just like not anybody could pick up the NES version of Ninja Gaiden and expect to progress in it.
Dark Souls will be the same kind of ass kicking, and I welcome the challenge.
Pick up and play is generally considered good game design. If a game is obtuse and hard to understand there is something wrong. Pick up and play doesn't mean no depth.