Bed, Bath and Beyond Coupons

Did you know that you can use more than one coupon in a single transaction at Bed, Bath and Beyond? I didn't. The cashier told me about it during my trip today. I was enjoying a blissful hour of shopping without the children, and I found 3 items to purchase. They have a fairly large collection of clearance items right now, and some are marked with a sticker to take an extra 33, 50 or 75% off the lowest price.
When I checked out, she used my coupon for $5 off any purchase of $15 or more from the back of a mailed catalog, then she scanned two of my 20% off any item coupons that I'd received as postcards in the mail. All three had expired, by the way. I knew already that they accepted expired coupons, but not multiple ones. This information could prove dangerous for my credit card balances...