I beleive the law only says that you cannot make 100% copies of currency. You can blow up a dollar and use it for an ad, or poster for carwash etc. or shrink it. But it is illegal to make 1:1 copies. Copiers that can duplicate some of the finer lines of currency I also believe have to be registerd with the Feds.

Most likely Kinkos put that in their softwre so they did not have to worry about it, or worry about emp's making "OT" pay.