Gosh! 20 years back my employer was doing this.
We were a book printers and had a book shop in the front.
Pads sold for £0.10 each.
My place of work actually gets paid more for the waste now from a waste collection company - fully installed industrial compactor, waste paper taken care off and taken away each week.
I did have a job this week that forced me to print in a SRA4 print area on a SRA3 sheet digitally.
This was due to the final trim size on the job being 15mm x 25mm (our guillotine did not come back far enough), so we used the subtraction method on the guilly to cut from the back edge in minus amounts. This enabled us to get the finished size we needed but we did have waste.
It was an after-thought that we should have put another job on the outside edge(s)!
It was also a one-off run but if it had been an often repeated run, we certainly would have printed another job on the same sheet!