Oleguy, you need to go back and read everything pertaining to section 210, specifically 210.23 There is more than one subsection that pertains to a laundry space. Yes, the machines can only plug into one outlet, but there are exceptions to what can also be done. And yes, you can use them as a convenience for an iron, and for a utility light. But what the OP wants to do, by plugging in a heater, they need to wire a Small Appliance Branch Circuit into that space. Whether it and the outlet for the washer/dryer is part of a multi-wire branch circuit, like I said before, there is a loop-hole in section 210, that you can wire a convenience circuit into the space.
In my case, my whole basement is a utility space, which means that the washer is not in a dedicated room, but I have a dedicated outlet for it. And trust me, the circuit is code, along with every other circuit in my house. When I leave, what the next person plugs into them is their business, but I know that how they are wired is by the NEC.
The only thing about the code, is that it does not stop a person from what they can and can not plug into the circuit, as long as they remember not to overload it, the circuit is still in code. If you overload the circuit, the OPCD needs to operate within manufacturer spec's, and needs to be sized properly for the circuit. Now as for what stops a person from swapping out a lower amp breaker to a higher rated amp breaker, is how soon the wiring melts from the overload. I have also seen 400 amp circuits melt bus bars, and the breaker looked like someone shot a 12ga through it.
I have seen properly sized breakers for the proper gauge wire melt & the circuit catch on fire. Why, because of the inrush of current caused by a surge, and the breaker will stay open, until it either gets too hot, or the circuit completely shorts, then it will close. That in case, is what a space heater will do on a 15 amp circuit. They should only be operated on 20 amp circuits, protected by a AFCI breaker, and with working smoke detectors in the home.