They are not legitimate pizza shops, all they want to do is steal credit card numbers.
Ah, OK.
In that case...wow. I can't believe they aren't doing more to stop it. I assumed they were real pizza joints just trying to get advertising.
Now I'm interested in this...I mean, that's going in to FBI territory. And if these people are all over these resorts doing this so often they have to warn guests about it - again, I'm seeing a severe lack of security at these hotels.
As to some of the other points -
1) Writing Disney is certainly effective, in fact, I'd copy your correspondence to both the owners of the hotel as well as Disney. While Disney may not be "responsible", they are still representing Disney in a fashion as it is on property as well as under the Disney Resort umbrella. While Disney cannot address it directly on their own, you are darn tootin' they want to hear about it and they would contact the hotel on your behalf as well. There is definitely an interest on their end on what goes on in the Disney Resort, and they have liaisons who would address it. In any case - more eyes are better.
2) I agree a lawsuit isn't in order, but an apology is. When it comes to complaining at Disney, if you are reasonable in your complaint (i.e. it's a "valid" issue, and not a "hey I had to wait two hours to ride TSM - give me freebies!"), it only helps other guest experiences in the future. From the sounds of this they need to step up security, but in a different way. Both Disney and the hotel need to know this.
3) To those criticizing the OP for showing ID, well, it's true we all need to defend our rights - on the other hand, I have my ID at the ready whenever at Disney as I am an AP holder, and if a security guard asked...it would wholly depend on the situation. If I have not done anything and have nothing to hide, I really don't care if they know who I am (though no one would be copying anything down off of it). The OP is young and did what she believed was the "right" thing. However, again, they need to let the proper people know that this is going on.