Just making hot dogs and baked beans on the fire
Sure, that can work. You can also buy potatoes, wrap them in silver foil, and toss them into the fire. But for most anything else (even plain hot water) it's much easier to use sterno.
Thinking of getting a mat to go on the floor of the tent
A mat or air mattress is certainly a good idea to get a comfortable night's sleep. The suggestion I was making though was to put something
underneath the floor of the tent (to prevent contact with the ground). You'll appreciate why when it comes time to take the tent down.