Because the stability control is constantly applying the rear brakes whenever it senses any motion it doesn't like. Combine that with rear pads that are 1/3 the size of the fronts and the rears wear out fast.
No. 87 E0, 87 E10 and 87 E15 are all 87. Refiners mix in lower octane components with to account for the higher octane of the ethanol. E10/15 is NOT 87 E0 with the ethanol dumped on top.
I wouldn't sweat towing a 4000 lb camper long term with the Maverick. It tows great. I would be much more concerned about spending 12-18 months in a 4000 lb camper. They're small.
Something tells me the "I'm willing to pay a ridiculous price with no economic benefit to virtue signal that I'm saving the planet" folks aren't in to camping.