...does your group provide the food...
Had a giggul. Just like ammo, you've got to pay to play and pay to be fed. So that means bringing your own food and booze to contribute to the pile. Often for larger units there will be a designated cook that will bring and cook food for a price and units that are in good relation to the cook's unit will be offered the food at a price.
3.PzG has one and we had some very good soup at FIG cooked up by them from their Gulaschkanone. The picture you posted is post-war as fuck. Here's the one they've got.
The three metal containers in the doorway (not the gasoline/water containers) are called "Essenträger" and my unit has one we use to store bottles of water, alcohol, and then occasionally other food. It's basically a huge heavy ass thermos you can wear as a backpack.