Englishmen overdoing the US accent

http://es.youtube.com/watch?v=tjDNHFViXBQ

A nice song, but there is a pronunciation mistake.
When Englishmen try to use the US accent, many times, they overdo it. So, in the song, the singer pronounces

quarter with an /A/ unrounded vowel (as in father)
This pronunciation does not exist anywhere in the US, the vowel is rounded /Q/ (like in or, war, door).

It's a thing that spoils the song.

Why is that? There are good pronunciation dictionaries. Is it laziness?

I knew a kid from Wisconsin when I was abotu 11 years old... the kid said "quater" for "quarter" rhyming it with "water" and we used to tease him about it. He, in turn would tease us about our southern-tinged speech. So maybe it does exist in the US. At any rate it doesn't ruin the song for me.

Aren't those guys German? ;)

I guess the singer is from the group New Order which is British.

This is less a pronunciation mistake as much as it is a reflection on the origin of the band in question. New Order is from Manchester, where the pronunciation is more open than either British or US speech--[kwQ:t@]. So if they add a rhotic to the end of that vowel, it's going to sound to an American like kwAR-ter.

kwAR-ter is the old St. Louis pronunciation

quarter = ''quarter''
highway forty" = "highway farty"

But it's dying out, even in St. Louis