Okay, my tuppence worth. I have contacted Disney because of the Tour groups, particularly in the days of the FP machine and being stuck behind tour group leaders with dozens of tickets, feeding them into the machine (helped by CMs) and watching the return time go later and later and later, then they all return to the FP for the ride at the same time, I went to go one Buzz Lightyear FP just a tour group arrived, a small number were ahead of me and the CM allowed the entire group (easily 30 or 40) to go past me, I said I was one person and he told me they wanted to stay together. They go around in these large groups with the group leader holding up his little flag and they think this gives them the right of way or they all stop at once and block entrances, pavements etc...
As for rowdy parties, I went in 2012 in March when the school parties arrive, mainly for day visits, I was on the ferry from TTC with several bus loads and they spent the entire trip singing and chanting very loudly, no one was happy, but, you can't say anything, they have teachers with them who seem to forget they are there to supervise (the same happened in May at Universal and these were even worse, they were an absolute nuisance in City Walk, especially at the Starbucks and I came so close to giving one teacher with them what for as she almost encouraged their disgusting behaviour by being their pal rather than chaperone)
The Mayor of Orlando, Buddy Dyer is encouraging these groups to visit the are as he thinks it'll bring money in, but, he is mistaken, the people adding to the economy are families and overseas visitors who spend money once there, many of the tour groups pay at the time of booking for things like meals that are subsidised by the numbers. The issue,for Brazilians, is visas, they aren't as easy to get as for Europeans, they tend to have to wait a minimum of 3 months from applying to get it, if they could get Estas then maybe they would come as family groups doing packages the way we do rather than booking through tour companies who do all that for them as it is such a palaver.