Pork is not really an expensive meat, but cheese, especially the processed block, value junk that is used for cooking. It is cheap and cheerful.
Lamb is probably the most costly. I haven't a clue why, we are surrounded by the little blighters. They are walk down the road, in the streets. When we go star gazing in the Brecon Beacon, National Park which is only a stones throw from where we live (to avoid light polution) the sheep are everywhere.
We have to drive really carefully as they leap out from the ditches at the side of the road. Suicidal sheep we call them.
Of course it is a different matter with 'live cheeses' they are not what I would term expensive but to expensive to just throw in the back of the fridge in the off chance that it might be used.
We tend to eat a lot of fish. Not tuna, I can't stand the stuff. Yuk.