We NEVER kick them out on the first offense. We always warn them politely first. The other day, we had a woman who, after being warned (and having her monitor deactivated), decided to give us attitude and try and snap photos of all of the monitors (even the ones that were not hers). We called security on her, but even she wasn't kicked out. I've been pestering my supervisor to buy us some signs, but they're not our biggest priority at the moment.
Still, this is hardly a minor thing - it's breaking copyright law, not just our own silly rules. Regardless, I never think less of a person for trying it once. I understand entirely, especially considering the lack of signs. It's only when someone scoffs or continues after being warned that I get photo-nazi on them. 65Skylark, I believe, handled this rather well. As for those of you who do not respect our rule or brag about breaking it, I look forward to enforcing it myself should we ever meet in person.
The only reason for bickering about CP's policy that I can understand is the issue concerning signs. That's why we always warn first - and that's why we rarely kick anyone out over it. Once they've snapped the photo, they don't NEED to break the rule again, at least not at that coaster (where they would recognize that guest). That guest, the one who gets his picture before we can dump it, has won. He needn't be after a high quality photo he can display on his mantle, he may have just wanted to show his friends the silly face he made or whatever. Either way, he succeeded in making use of it without needing to buy it, and he is free to do so at any other coaster he wants since each one has a different crew and will have to assume it was his first offense. Rather than dismiss EVERYONE from the park the first time they try it, we warn them first and thus pretty much allow EVERYONE to get away with it, as they only need to do it once to get what they were after.
Still, we have kicked people out over a few circumstances - one involved a person being transferred to cover a break at another coaster only to witness a guest they warned earlier repeat the offense after not expecting to see that employee again. A few others involved guests snapping more photos in rebellion after being warned - that sort of thing we have very little tolerance for.
Just remember: we took these photos, we have every right to keep them to ourselves. No one has any "right" to take pictures of them, even if they weren't planning to buy them anyway. If you want your friends to see it, remember your number and we'll be glad to help you show it to them later. Even if you don't consider it "wrong," it is at least very rude to photograph someone else's property without even asking.
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By the way, as for those of you who admit a disregard for this rule, I think we have a precedent to appeal to on this matter. Remember the "getting away with a POV" thread, and Robb's response?