I was too slow with my edit so I will repost here:
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Hypothetical Situation:

Coffee shop owner:  "OK, that'll be .7865 DASH please.  My address is Xkh65Rfk8...
Me:  "OK, sent."

Coffee shop owner checks his wallet and .7865 DASH appear.

Is his response A) "Thank you, come again" or B) "Can you cryptographically proof you sent me the funds?"