English phrase "Can I help WHO's next?"

[Guinevere]

In what part of English speaking world can you hear "Can I help who's next?" in, for example, fast food shops?

[Mister Micawber]

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There is extended discussion on this, as you know, HERE.
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Native English teacher at Mister Micawber's

[Yankee]

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I can vouch for the fact that this is a very common sentence in Connecticut (USA), but not just in fast food places. You hear it wherever there is a line of people waiting for a cashier -- cashiers seem to be particularly fond of this sentence.

After reading the other threads, it seems this sentence is common in many other places in North America too.
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[Torsten]

There seem to be quite a few explanations as to the origin of this phrase and to me it sounds like two separate questions that are being asked in quick succession: Can I help? Who is next?
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