Because it gives people financial incentives to fulfill others' dreams:
Roller coasters and ferris wheels are all very well as entertainment for some groups of consumers, but for others, there's nothing quite like the experience of operating heavy machinery. That, at least, is the premise behind Männerspielplatz, an amusement park for men that lets them get in touch with their inner construction worker.
For EUR 219 [around $300], visitors to Männerspielplatz can shed their office trappings and get seriously dirty while playing with excavators, wheel loaders, Caterpillars, quads, Jeeps and more. The park, which is situated in an old factory site just outside Kassel, Germany, offers 18 stations for visitors to enjoy to their heart's content. Challenges include using a Komatsu Hanomag excavator to move huge stones; leveling the ground with a bulldozer; off-road riding on a Quad Unimog; and participating in an archery course.
(via Doug Ross)