Before posting, I did a cursory online search and did find the following CFR language - 36 CFR 2.13 Fires (a) (2) Only chemical based camp stoves may be used.

I suppose alcohol is a chemical - perhaps a slightly modified can is not a "stove"??

I do recall seeing somewhere that permissible stoves had to have an on-off valve....

None of this bureaucratic twiddle will prevent some doofus from starting a fire in circumstances that are clearly inappropriate.
Geezer in Chief