requires no training and no ability to pass exams, understand technical things, etc.
That could be argued
Ok, so in theory, anyone could go out and buy a yacht, and sail off into the sunset, but in practice, to get a yachtmasters ticket, the exams are far tougher than anything I encountered in the PPL. The Nav for example is at a far higher level, no multi-guess, and the physics is actually comparable to flying, when you take into account forces generated by the sails, by the keel, by the tides, curents, etc....
I agree that sailing and flying are different, but the thing they have in common is the high costs involved. If it has the word Marine or Aviation in a products title, you can bet the price has been inflated by 100%
CheerS
EA