Give "Makeshift" Tupperwares a try.
You take two beer case boxes like these.
Get a roll of tin foil, heavy duty type is preferable.
Tear either 1 or 2 equal lengths of foil. This depends on the width of the box and tin foil. You will need it to seamlessly cover the bottom of the box and sides. If you need 2 pieces to do the job then lay the two edges together and folder them over a couple of times to join the 2 pieces.
Line the inside of the box as shown.
And there you have it. Use the other box for the top as a cover.
Container all covered up protecting the contents.
There are many advantages to this type of container. For one, it's cheap. You don't have to worry about taking it back home. No clean up. And the most important reason to use this type of container is that it will give you another excuse to buy more beer so that you will have plenty of meat and food containers on hand at your BBQ. Word of caution, soda containers will not work. For some reason the food doesn't hold as well. Better off sticking with the beer boxes (Just a funnin').
Until next time....