How about the paper used in working places (every worker use paper and some more than other)?
How about the paper used in schools?
How about bath tissus or paper tower?
News paper? Books?
I don't think drawing artists are the biggest source of paper losts!! Also there are ways to minimise you're use of paper liske use both side of paper (when you're not drawing something official) or use recycled paper... We should cut on many other things before to cut on the drawing paper ...