If it's a harmless resurrection of a sweet old tradition, which I'm prepared to accept that it is (maybe!), then I think it's worth mentioning that the words "ask" and "permission" are a tad misleading. If it's just about telling rather than asking, why not use the word tell and both prospective partners do the telling?
Also, why is no-one mentioning it being done the other way, by the prospective wife to her prospective mother-in-law.
While ever it is or even looks like a one-sided tradition you can't really expect modern-thinking people to accept it as not just a wee bit of a patronising and paternalistic tradition that they'd rather had buggered off into the sunset along with other traditions that seem not to favour equality.