Ive been a transportation CM at MK and have been involved in what some of us like to call "A Mass Exodus" which is when 60,000 people try to leave the park at the same time, I have a few rings to add.
1. In regards to setting up extended queues for buses, do you have any idea how long it would take to set one up for each and every resort bus? hours, unless you want to use 50 CM's to do it then you could get it done faster. That would also require a ton of stanchions, and need a lot of storage. Queues can be quite difficult to set up and may take a long time unless you've done it dozens of times, just look at the extended queues they use at TTC in the morning, the one for the ferryboat takes nearly an hour for two people to set up.
2. Its borderline chaos after wishes anyway, it may not look like it to guests but trust me it is. Setting up queues just organizes a tiny bit, and with the way MK's bus loop is set up they wouldn't do much good.
3. I've been one of the CP's standing behind the podium saying you have to wait till the next boat, 97% of people are fine with being stopped and will listen, but oh the other 3% are something else. (I got berated once because I stopped the stroller line to let more regular guests on the boat, that was fun.) Ive also been the guy standing with the orange wand, thats even less fun than being behind the podium, when it gets busy guests won't listen, a hundred CMs could be standing there trying to direct guest flow but the overall mentality of guests will be "Im at Disney, Im paying thousands of dollars to be here, I can do whatever I want".
I know some will say well they can just do what they do on new years and the 4th if they need to get people out fast, well they literally start setting up for those holidays days before they actually happen, they schedule triple the CM's they need for crowd control, and open shifts for more if anyone would like to pick them up. Transportation is a well oiled machine when they can plan ahead.
And regarding the resort guest issue, You are a "Resort Guest" the moment you drive on disney property. In order to keep your car at a resort you have to be an "Overnight Resort Guest" of that resort. You can not just park, have a drink then go to the park for 8 hours, that is against policy.