I don't know how it's the worst ice compared to say the Staples Center.
That place has 4 pro teams playing there. I'm sure multiple events, and in a warmer climate.
The climate actually doesn't usually effect the ice as much as you'd think. The ACC appears to be pretty bad ice. Having 4 pro teams doesn't help but lets remember a place like MSG I'm sure is used pretty much every day for concerts and other events. Edmonton has the best ice from what I've read.