I wouldn't blame proprietors for banning loft during open bowling and possibly even recreational leagues. Obviously, open bowlers are probably just doing it for fun, and I've never encountered a league pattern that truly requires that type of play. Now, when you get into the competitive arena, I think it should be allowed as needed.
I liken it to soft spikes versus metal in golf. I haven't seen a golf course that allows metal spikes in about 20 years, yet the pros are allowed to wear them during tournaments. The average duffer like me should wear soft spikes to protect the greens from damage. Pros should have the option. I see loft much the same. If their is nothing of significance on the line, no extreme lofting; save the lane surface. If we're in a high-stakes league or tournament, let them do it as long as it's being done to play the lanes, not out of frustration or for entertainment value.