Oh, believe me, those same types of people who don't like 'Americanisms' are the very reason most regional dialects have died out.
It's snobbery, it's been applied to all regions of England with an accent that isn't 'quayte nayce' (which, by the way, is written in the accent common to Royalty, which actually has it's roots in Germanic mispronunciation).
It's been applied to the Scots, the Welsh and the Irish, to the point of denying entire generations the opportunity to learn their own language in their own schools.
For those of us in England, from a rich and varied distinctive dialectical variances, we have been left with smatterings of vernacular that, if it were up to these people, we'd be prohibited from using in public.
Whilst it is necessary in the modern country where we all move about much more than we used to, for us to understand one another, therefore some standardisation had to happen, this attitude that 'our' language must only be spoken in a certain way has its roots in deeply embedded class divide.
I apologise to all Americans, but you are only going through what every person in this country who has a regional accent and uses any form of local vernacular, has gone through in this country .