(2) Laundry Branch Circuits. In addition to the number of branch circuits required by other parts of this section, at least one additional 20-ampere branch circuit shall be provided to supply the laundry receptacle outlet(s) required by 210.52(F). This circuit shall have no other outlets.
It does not specify what, in that laundry area, can or can't be plugged into one of those receptacle outlets.
The intent is that you have enough available power to accommodate the normal loads you have in the laundry, a washing machine and an iron, mostly. I do not see small cord and plug auxiliary loads from gas fired appliances being a problem. If they plugged in a 110v electric water heater we would have to talk. That does infringe on the 50% rule for fixed in place appliances in 210.23(A)(2). Bear in mind 210.11(C)(2) does say "receptacle outlets" and "no other outlets", so you can't have any hard wired equipment on that circuit.