I've heard the repeated argument that the Square Format "wastes" so much paper.

There is always a flip side ... the Rectangular Format "wastes" *so* much of the lens image ....

So which is more important - the lens field, or the paper?

Y' pays yer money and yer takes yer choice ...

Oooops ... I forgot we have many international members who might not understand that ...
It was a common cry from Circus sideshow attendants to try to get participants to "throw the balls at the bottles" - and if you were successful, "You paid your money, and you seleted whatever prize you wanted.