I have found that it is never safe to drive away from a McDonald's...ANY McDonald's, until you check your order...just my experience. In the past, I just get myself out of my car and march myself back in and ask them to correct my ordere...it's usually that they have tried to pass of cold, hard fries onto me, and I won't let them get away with it. I also ask for the manager to let them know why I've returned and also call the owner of the restaurant...this is posted in the restaurant. I mentioned "in the past", because, frankly, I can't remember the last time I darkened the door of a McDonald's. I always try and remember why I've been aggravated with them, and then I drive on to someplace else.
I've seen a lot of the same type of hygiene lapses that you mention here, at other fast food places, as well. For instance, I've witnessed, at a BK, an employee mopping the floors, and then heading directly behind the counter to handle food orders. Who trains and/or supervises these employees who do this sort of thing? I've seem DQ employees (these people have to be the sloppiest, dirtiest looking, fast food employees on the planet), wipe their hair back off of their faces and then reach for a cone to fill my order. I really got angry with this and told the employee about it. These owners/managers whom leave their stores to be run by kids, with no supervision, and who have absolutely no work/hygiene ethics, are ruining their businesses, as far as I'm concerned. I avoid these places like the plague.
Congrats on your winning letter of the month, as well as for exposing these lackadaisicals.