Ken found this great feature and almost managed to keep it secret from us.
In Retail Pro 9 any time you’re in the LIST VIEW of documents and want to print several in bulk (ie, print all receipts filtered for one customers on a charge account) you can use the ALL LISTED RECORDS button provided you have the option to change the printer selected in WS Prefs. Just make sure the last band on the design is set to “Page Break after Band”.