Difference is, the buyer haggles after receiving the non-returnable service, so they cannot shop around, or use the threat of shopping around as a bargaining ta

Difference is, the buyer haggles after receiving the non-returnable service, so they cannot shop around, or use the threat of shopping around as a bargaining tactic. The buyer is entirely captive, while seller may freely decide how low to go (if at all), depending on factors opaque to the buyer.