I just don't get how people do that.
Same thing kind of happened to me at Okemo this year. Come out after lunch and my skis were gone....and there was another pair of the same model and length a little further down the rack. Although the bindings were different, the boot size was the same. The idiot just grabbed my skis, clicked in and went, without realizing he had the wrong skis. I just don't get it. Sure, they may have been the same ski, but every pair has something unique (tag from the shop for one) and to not notice the bindings were different? Please.
Had to report it to security, file a report, blah, blah, blah......and they said if my skis didn't show up I'd get the other pair. Fortunately the moron realized he had the wrong skis next time he stopped, but it still screwed a couple hour of my day. The shop at the mountain loaned me a pair for the afternoon and I was just skiing with my 4 year old during that time, but it was still a pain in the rear.
Hope you get your skis back.