What kind of module was it? If it's something that doesn't fail very often, they probably would indeed have to send a guy out into the yard to get it. As opposed to the stuff they pull immediately and keep on their shelves (head- and taillights, bumpers, seats, wheels, front core supports, etc, etc) which is the real bread-and-butter of their business. A nickel-and-dime module they sell one of every three years just wastes a guy's time for an hour, locating the part in the yard, boxing it up, etc.
About this time last year, I needed a body control module. I found one at the local U-Pull-it junkyard, and it was just $24, but I probably spent an hour searching the yard for exactly the right car, and then pulling it from underneath the dash. Not as easy at it used to be when I was younger and more flexible. We should also factor in the tools I bought (years ago), the $2 admission fee, and gas I burned to get there and back plus however much I value my time for 45 minutes of driving each way. Eventually, the $50 price you paid looks good just for its convenience.
By the way..... The module I needed sells for $106 at Rock Auto for the actual AC Delco part.