I don't know that we can consider different ways of speaking as necessarily incorrect. It used to annoy me that merkins said alu.mi.num but then discovered that that was how the Englishman who discovered aluminium originally spelt and pronounced it.
It used to bug me that Jamaicans would pronounce "ask" as "aks" but then discovered that "ask" was spelt "axe" in mediaeval England.
It still does irritate me when people say "prehaps" instead of "perhaps" but p'raps that'll be how it's spelt in years to come. The same goes for mis.cheev.i.ous when, in fact, it's spelt "mischievous".