I did something similiar, I named all the printers with an esoteric naming scheme based on the OU and location, but completely indecipherable, and GPO reset the default printer every morning. That way the print was always released to a random printer that the user chose in utter bewilderment and confusion, so there was no chance any particular printer would see enough use that I'd have to change the toner in this decade.

Worked great.