I have to call bull

on that hot tub story. First of all, Disney/Marvel actors all have handlers that are paid by DISNEY and their jobs are to make sure the stars are protected from scandal or bad press and that means that things like you describe don't happen. Second, Disney/MCU stars do NOT stay in the same hotel where the conventions are held. Most conventions are held in mid-range or economy hotels and the stars would stay at nearby luxury hotels and be brought in for events. I'm not talking about D-Z listers that are manning booths, selling meet and greets, and "remember this show" panels but the A-C listers and they are not staying where random fans can find their rooms. That also means very little "green room" time for a star like Tom since he'd meet up with whoever was also on the panel at another location and be delivered to the stage in time to make an entrance and then escorted back immediately after.
Even if the star hung out and made themselves seen at a convention, you can bet security and their handlers are never out of sight.
Finally, in an era of plentiful cell phones, sexual harassment allegations, and instantly uploading to social media this kind of thing isn't happening anymore. These guys are in BILLION dollar franchises and they have extensive training on how to handle fans and rule number one is DON'T PUT YOURSELF IN A POSITION WHERE YOU CAN BE ACCUSED OF SEXUAL MISCONDUCT.