The problem with people being able to keep virtually any animal as a pet means that there will be a lot of people keeping animals in completely unsuitable conditions. You get that anywhere in the world already but the more extreme the animals that can be kept the more likely many of the more exotic ones will be kept in unsatisfactory conditions. Unfortunately there are people everywhere who get bored with an animal and release it. I personally don't have a problem with NZ banning tree climbing, native bird eating reptiles for that reason and it may be that the USA has concluded that the freedom to keep any animal you wish can have its problems. So a few tiger breeders will be looking for new employment but they will be a lot fewer than people in many other more usefull jobs.