I hate when escalators are blocked off for no reason... I was at a mall where they were all blocked off so you had to go to the entire other end of the mall to use the one elevator for the entire mall!
Unless they're actively getting worked on, just leave them as stationary stairs if they're not working! Just makes the entire place more unfriendly to people visiting...
I'm certainly not an expert either, but logically an immobile escalator disconnected from power is (to borrow the Mitch Hedberg bit) simply stairs! They don't block off stairways in buildings and force everyone to use the elevator...