I don't throw things all over, but I've brought pizza or other takeout to my hotel room. The best thing I can do is just leave it on a table or on the floor next to the trash can. If there's a receptacle in the hallway, I don't think it's meant for for collecting stuff that was in a room. There's a reason why housekeeping carts have two large bags - one for the used towels and the other for all manner of waste including stuff that won't fit in those micro cans that are typical of a hotel room. Used towels are supposed to be left on the floor.
Housekeeping doesn't have an easier task just because a guest tidied up. They always have to remove the sheets anyways, so trying to make the bed just adds extra work.
Besides that, I doubt that most car rental returns like having customers with their hands full of garbage as they're exiting the car and then having to empty trash cans. As long as it's easy enough to toss into a trash bag and give a quick vacuum, they really don't mind cleaning it up. Maybe I'll leave a throwaway map in the center console or a bag with wrappers and napkins. I will try to at least tidy things up so it's not all over the place, but I have no qualms about leaving it in the car as long as it doesn't stain anything.
This is expected. There are people paid to do this job, and as long as it's not a disaster area they really have no problem doing the job. Often attempts to help them out create more work. Here's an interesting discussion on Quora:
https://www.quora.com/Do-hotels-maids-prefer-that-I-leave-the-room-cleaned
Assuming we are talking about checkout day, the worst thing you can do is make the bed because the room attendant has to UN-make the bed. If you are staying over and it makes you feel better, make the bed and leave a note to not change the sheets. They will usually tidy it up the hotel standards. If you want to help the room attendant on the day of departure, do the following:
- Strip the sheets off the bed and pillow cases and leave in a pile on the floor opposite the bathroom door.
- Take all used towels, washcloth, and bath mat and place in one pile on the bathroom floor.
- Take the trash can from under the desk and the trash can from the bathroom and place them together next to the sheets (by the bathroom door).
- Replace the iron and ironing board (wrap or retract cord of iron)
- Replace the tv remote to where it was on checkin day
- Open the curtains.
You have just saved the attendant minutes and her energy by saving her the steps she has to take to walk to the other side of the room to grab the trash can and walk back to the other side of the room. Stripping the bed takes little time but again, energy. Finding the remote and walking it back to place...energy/time. Ironing board and iron...energy and time.
She would appreciate these steps probably more than a tip.