I agree with the OP. I usually go out of my way to support businesses that support the RV industry (I have a vested interest). However, slow check out at any business is a pet peeve of mine. It just seems strange that the taking of my money is the slowest part of many transactions. Walmart leads the way for me. They build the stores with nearly 100 checkout lanes and you are lucky to ever find three of them open. At a Walmart, the worst sound you can hear while standing in line is the cashier shouting "Price Check".
I agree 100% with the premise of this thread. If I am willing to give you money, please find a way to take it quickly.