The threat to the perpetrator -- of 90 days prison time and a permanent criminal record of being a mischief-maker -- prevents people from pulling the alarm.
Sure, and to circle all the way back to the original point several posts up - why is this a deterrent to someone pulling a fire alarm but not for someone sending a fake UDP broadcast? The penalty will be exactly the same.
Harder to track down the person. Unless the hotel is logging every packet on its network and paying to archive the TBs of encrypted video streaming data that goes through every day. And it's a purely local network, so not like the NSA can help out.
Edit:
"Unauthorized" computer access is a serious federal crime under the CFAA, and that you did it as a joke is not a legal defense. Famous examples:
Same way sheepdogs herd sheep.