I remain unconvinced that this is a rip-off, and for people to single out MAN as the Dick Turpin of airports really shows their level of, or lack of, knowledge.
Rover wrote an excellent contribution earlier, and little more can be added.
Truth be told, unless you are heading off to certain specific destinations with your 4 cases, a widescreen TV, a VW diesel engine and gifts for your extended family, how often does the average passenger honestly require a trolley?