This thread seems to be progressing along the lines of the previous 100+ threads that have been posted on the same, identical subject; although it appears that the mods have been doing a lot of Housekeeping. Too bad the search function was glitching, or the OP could have saved a lot of space and simply added on to the already active thread on the TRANSPORTATUON BOARD, where this subject belongs.
In keeping with all of the previous threads, I will add this thought: Seats on buses are disappearing. Every new model bus that comes along has fewer seats than its predecessor. This is as true at WDW as it is in the real world. Why? Because buses are designed for mass transit. As in: getting the largest number of people from one place to the next as fast as possible. How do you do that without doubling or tripling the number of buses? The most cost effective way is to increase the number of people per bus. How do you do that? By reducing the number of seats, because a bus can hold a lot more standing passengers than sitting ones. A PPs description of the London Underground is a prime example.
Robo may not have been all that far off the mark when he suggested that nobody gets to sit. It just might happen some day. Until then, I would suggest that you refrain from judging those people who don't offer up their seats. Unless you are intimately acquainted with their full history, you have NO idea why they remain seated. Confine your judgements to your own group. And if you are unable to stand on a bus, take personal responsibility for your own safety. Disney transportation is provided as a courtesy. If it doesn't meet your needs, there are other options that you can choose.