"Sure, I'd like to see the draft move around (to other cities), and I would love to see it come to Pittsburgh some time," said Rooney. "It's a great event and attracts tremendous fan interest. It would be a fun event for Pittsburgh to host, and I think our city could do a great job with it."
It's not as if the draft has any sort of geographic priority, and if the league is using the Super Bowl to leverage cities into building new stadiums (hence the reason Super Bowl XLVIII will be held in New York), it may as well follow it up with moving its yearly bonanza of young talent to other locations.
The cost of shipping all the league employees required to put on the event to a different city may be a cost the league doesn't want to take on, but considering the revenue it generates for what's arguably the largest production for the least amount of required coordination (the draft literally used to be held in hotel conference rooms with the commissioner announcing each pick to the general managers in attendance), it seems like they could share the love a bit with cities of teams who would otherwise never get to host a league function.
The Super Bowl is never coming to Pittsburgh. It should never be held in Minneapolis or Cleveland. The NFL Scouting Combine will never leave Indianapolis, so why not move the draft around a bit?