It sounds like you went to a lot of effort just to avoid wasting a small rectangle of paper!
I've had quite a few jobs done to the house in the last couple of years and although I always offer cash, not one of the tradesmen (including the roofer) has been interested in taking it. The carpenter who built me a new porch said that cash was a liability for him, he didn't need it for himself and the banks suspected him of money laundering if he tried to pay it in. All of them used an online system that sent me an email bill payable by direct transfer.
