This is more of a must-click link thing, because Ben Badler is the expert here and over at Baseball America he explains how teams have, since the dawn of the international bonus caps in 2011, circumvented the rules.
Not surprisingly, the way rules are circumvented enrich some — trainers; owners who are paying less for international talent — and cost poor, young players. Nor surprisingly Major League Baseball doesn’t really enforce its own rules that much. It would if bonus expenditures were dramatically enhanced, but breaking the rules here and there to get around restrictions appears to be less than a petty misdemeanor in the eyes of the league.
Like anything else: when you make rules which restrict what people would be doing anyway (i.e. spending money to get the best talent) people are going to find a way to do what they wanted to do anyway. And when that happens, it’s probably a good idea to look at the rules and ask what the heck the point of them was in the first place.