[o_zarkman44]

how about the posting of signs at the entrances of businesses that say "English ONLY"? Bumper stickers "English Only Car"?
Gosh, would revenue fall for those businesses that post a language preference? Is it unconstitutional to deny immigrants based on the inability of Americans to communicate in foreign languages? By some standards....... probably so. Gotta draw the lines here. America speaks English, the language of opportunity in America. Learn it.

[DumpsterDiver]

how about the posting of signs at the entrances of businesses that say "English ONLY"?

I'd skip the signs and simply stick to speaking English to all customers. If they don't understand, then those are the breaks.