Oh, for making things easier, I have been looking for smaller packages at reasonable prices and deciding on a menu that doesn't more than a few things for each meal.
I will bring the picnic size salt and pepper and leave them there. Kroger has the most popular spices in small-sized generics for $1. I found room service style mustard, ketchup and mayo at
Walmart (50 cents ea) and bought the mustard and mayo. I bought a small ketchup (but larger than the room service size) for $1. I can trash all of those at the end of the week.
Muffin mixes in pouches take up less room than muffin mixes in boxes. And now you can buy disposable muffin tins just like the aluminum cake ones. I will wash them to reuse while we're there, but they won't come home either. With luck, I'll find a recycle bin for them. Taking your own mixes is much, much cheaper and smaller than buying and bringing premade muffins. The same holds true for cookie mixes, and a cookie sheet is flat enough that it takes up almost no room in the rubbermaid bin.
Individually wrapped items like single serve twizzlers and slim jims can be fit into any number of small spaces in the Rubbermaid container. Just rubberband them to keep them neat.
Spaghetti only requires a jar or two of sauce, a box of pasta, and some meat - no spices. Hamburgers or hot dogs with fries and baked beans only needs meat, buns, a bag of frozen taters and a can of beans. Hamburger Helper is easiest of all - 2 boxes of HH and 1# of ground meat (and you can make it with ground turkey to make it a bit healthier. None of these meals requires special equipment or spices beyond salt and pepper.
I figure I'll still have room in the top of my bin for other things that won't crush the foodstuffs. And I'll have most of the bin for souvies on the trip back home.