Why are simple rides more money?

Why do the rides like the skycoaster etc. cost more money if they are much cheaper than the rollercoasters to build? Is it for insurance purposes?

I'd think capacity more likely: a roller coaster can take 20+ people on at a time, depending on the number of trains, cars, blocks, etc. A skycoaster/slingshot, however, can only take 1-3 people at a time. Less people = higher cost to see a decent profit on the attraction.

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Po!nt of View: A different look at Roller Coasters.
http://www.crosswinds.net/~justmayntz/thrills/index.html