Hello,
I think your house sounds like a great place to spend the holidays. I bet your family really looks forward to staying at your house. Honestly, it sounds like they have no idea that everything you provide for them each year is really a hassle to you or gets on your nerves. (not in a mean way)
I agree they "should" realize this, but they probably don't. I bet they would feel really bad if they knew this was how you really felt, and would happily pitch in if you asked in a nice way like people in other posts suggested.
If I invited people over to decorate cookies and they all came over and we decorated cookies together then they left and I was frustrated that I always have to buy all the cookies and decorations, it wouldn't be very fair to them. I'm sure the guests would feel really bad if they knew I viewed them as ungrateful guests. It probably never dawned on them to bring something if I asked them over for a cookie party. Especially if its an annual thing and I always provided everything. Now in a perfect world I would love if they would think to offer to bring something, but I wouldn't expect it unless I asked nicely.
Honestly if I didn't have the funds to pay for the cookies I should have said something like, "lets do cookies at my house. Would you mind bringing some icing?" Etc and ask someone else for some sprinkles and so on. But to not say anything and the unsuspecting guests come and have a great time at the things you offer them, then leave and then talk about what they didn't do makes me feel sad for them.
No offense to you, I so get where you are coming from and it's so kind to let them come to your house and provide everything. They are probably creating lovely memories at your house, not realizing they are the guests from heck.
I always love to read pet peeves posts just to see if I do anything that is a pet peeve and don't realize it, so I can learn from it. So I cringed when I read your post because I felt bad for the guests who really had no idea that when you bring out the snowmobiles that its a sore spot with gas and them not going outside. They probably viewed it as a magical experience with their kids having a great time with your husband and family outside.
I always feel uneasy for this reason when invited to someone's house hoping I'm not stepping on toes, or doing anything wrong that they are secretly thinking. My sister has her house perfect, and will wipe down the walls while you are sitting there talking or mop under the table if you drop a crumb before you can bend over and pick it up.

I am sooo self conscious over there. I can only imagine what she says when I leave. I once heard her talking about how mad she was that so and so walked into her living room and messed up her sweeper marks. I would have never realized that I couldn't walk in the living room and cringed to think how many times I may have walked in there not knowing I would be the talk of the house after I left.
I would much rather know what I'm doing wrong, than to have everything seem to go well but after I left know that everyone was feeling I was an awful guest.
Your house seems great and I think they all make magical memories there every year. Please perhaps follow the other great advice on here about how to nicely approach them bringing things. For the kids if you first smile and show them the punch bowl and explain there is plenty for all but to please take a small amount at a time and then go back for more. Then you can gently remind them again if they leave big cups sitting around. They will get the hang of it.
I'm sure many happy memories are made at your house at Christmas! That is a gift that is priceless!