Lowbrow? This is probably the wrong place to describe any traditional art as lowbrow.
Panto has survived for exactly the same reason that folk music has survived - because it's good.

It is one of the finer forms of theatrical art. One sees a better class of acting at the Panto simply because the players can relax and do their own thing.

Unfortunately a lot of the humour isn't understood on the west side of the pond, so it might be risky to try to stage a Panto over here. You'd have to have an interpreter, or sub-titles, to explain why certain things are funny.