People tend to thinks that the more they pay, the better product they will get, well, generally, it is considered to be true, but not necessarily in the market of consumer electronic as market is flooded with copycat products, so the product which costs high may not be equally of good quality, like phone cases.
For example, iPhone cases being sold on https://www.apple.com/search/Case-for-iPhone?src=alp is really expensive, but those copycat using bad materials and containing no tech will cost no more than 50 cents. Most people have no idea how to pick up a proper case, so I'm gonna say that, a proper case must be qualified both in quality and price. When you pick up cases that are really expensive, you'd better know whether they're worthy or are just copycat ones, thus not to fall into traps set buy sellers.
Usually a copycat case will not have the same quality as a genuine one to some extent, they may look similar, but there will be a lot in difference like material, crafts and details, etc. Unlike genuine ones, those copycat cases are really bad in quality, though look alike, copycat cases will be more easily to be worn out, which means they will be less durable, and when you buy such a case at high price, you will be totally regretful.
As for those cases being sold on apple.com, they are really of better quality than cheap ones, and when you can afford one without any pressure, you can take what you want freely like Otterbox, Casetify, Lifeproof and Sonix, etc., as they use real good materials and do have real good tech, thus to protect your device better. But on the contrary, people should be aware of how much do cases really worth, as those brands will set prices much higher than their real costs, taking brands and marketing cost in to consideration.
For wholesalers, visit: http://www.mocel-case.com/products, you will find what you want!