I can guess the answer, but... What is the power requirement to run a 2504 WLC, and is it possible to do with PoE+? Technically you could get 30W+30W if you run multiple interfaces in LAG mode...
Actually, it looks like uPoE does support 60W on a port, so technically a 2504 could be powered on a 2-port bundle (I gather a 2504 may use 80W). If this was the case, they'd have to disable the 2 PoE ports on the front of it...