Would this make transactions easier, or rediculously and unnecessarily complex?

As a cashier I tend to give people the money other people just had moments before. Technically it would be possible for people to skip transactions. Here is an example transaction:

Joe gives me $10 for his purchase and receives no change. The next person, Juanita, gives me two $20 bills for a $30 purchase, and I give Joe’s $10 bill to her as change. Technically there would be no real difference if Joe had just handed the $10 to Juanita.

A league off I think this could save energy somehow?Anyone have any ideas?

I understand that there is a certain amount of knowledge that is required that Joe could not have known, I see that. However, let’s say there was a cash network. The members of this network would notify the network about upcoming transactions. Then the network would evaluate all the members making a transaction and suggest an action.

That is just one thought. I think it is probably a void concept.