Frankly, if you receive a modest stack of BREs including orders and checks.
One solution: I knew a publisher who printed a "prospect code" on his BREs.
In the last survey I did on the question, 95 percent of consumer titles included a BRE (although I see what might be described as a mini-trend among smaller titles to make it a "courtesy reply envelope" rather than post-paid).
The response there showed that only about 50 percent include a BRE in the package.
In that instance, as well as for "Bill my company" orders, including a BRE makes it possible for the prospect to complete the order, insert it into the BRE, and toss the envelope into the outgoing mail without ever involving the accounting department.