Does he do the grocery shopping? Not much he can do about it if he doesn't.
Seriously though, Mr. Clod was resistant too, but as long as dinner tastes good, he just kind of stopped noticing that it never happened to have dairy in it... plus he gets his fix while he's out at work. It's really about how resistant your son will be, and how determined he'll be to hunt down dairy if you take it away. Maybe your husband can keep a minifridge out in the garage with a lock on it.