Cruise cabins are built exactly like that. Pre-assemble, install, tweak, sail 
Going up to fluffier/fancier towels adds way more to the laundry costs than you would think. Industrial laundry machines at hotels are pretty much run at maximum loads and any increase in weight of the items to be laundered means you’re running extra loads and increasing your expenses for energy, maintenance, consumables, and labour.
When the hotel I used to work at went to really nice towels the laundry costs for towels nearly doubled and the rate at which towels became unacceptably soiled increased noticeably (since we couldn’t bleach the hell out of them as easily). The GM felt it was worth it in terms of guest satisfaction, but a lot of properties couldn’t justify the expense.
I haven’t noticed this effect. I think you are just seeing the practical reality that there are only so many ways to combine the basic building blocks.
I’ve noticed that every hotel room I’ve stayed in has carpet for the baseboards, where as a typical house has wood molding. Why the carpet? Is it just less maintenance?
If assume the following:
- Hotel owners want as many guest rooms as possible, for the given budget.
- Hotel guests want the main part of the room (bedroom?) to have a window, preferably with a view of the outside.
then I think you’ll naturally end up with the “standard” layout. You want to cram as many guest rooms as possible within a limited size building, but still give each guest room at least one outside window. So you make each guest room as narrow as possible, with a window at the end. You make that end of the guest room the “bedroom”, and put the bathroom and closet near the other end.
It doesn’t show marks from the vacuum cleaner hitting it, which happens every day.
I think it’s to the benefit of the guests for hotel rooms to be so similar. It makes it easier to navigate the rooms at night.