Haha, Canon does have nice document scanner. My recommendation often depends on the size of the office and their scanning needs. The bigger they are, the more they prefer a centralized/managed/scanning system like a commercial MFC Xerox/Canon/Sharp/etc. Often, offices of that size have some sort of contract with their local copy/print company. Scanners and Copiers go hand-in-hand.
Personal/document scanners are often preferred by smaller offices (Something they can keep near their computers). I like the Brother because it requires no interface to any machine. Really great for a lot of security reasons.