I thought something similar. I mean, I bring diamonds to Disney, but they are in my ears, on my finger or around my neck - all the time.
Now, I think the cruise may be a little different, I might haul some of my jewelry along for formal night. And I suppose that if you went to V&As or something at Disney, you might have occation jewelry along.
But I'm sure there are people out there who do travel with their precious gemstones and change their jewelry. And people who travel with a lot of cash (I'm rather forgetful, so I never carry more cash than I can afford to lose - left too many purses in restaurants to carry a lot of cash). Neither seems wise to me - and with secured credit cards, travelers checks, the ability to drop cash on your room account, it doesn't seem necessary - but not everyone is educated about their options.
And, I'm sure that on occation doors at Disney get jimmied, safes get broken into. With the thousands of guests and CMs floating around the place, not everyone is honest.
Just because it doesn't happen again doesn't mean it didn't - if it was another guest than you wouldn't necessarily have a pattern - say it was a guy away from his family for the afternoon taking advantage of no eyes. And just because we didn't hear about it here doesn't mean it didn't happen again - we are a small subset of Disney guests. And the OP reporting the Orlando police instead of the sherrif being there doesn't bother me - how many people really know the difference and would take note (the police around here were blue, sherriffs wear brown and to my uneducated eyes, that is the only difference).
But I'm not going to lose sleep over it - I'll take the same precautions I always do - don't carry much cash, don't bring a lot of valuables on vacation, keep the door latch closed when the room is occupied. You can get robbed at Disney, or you can get robbed at home.