USB connector to do what ?
Apple has the "iPad Camera Connection Kit" featuring a USB port. There are also various third-party options floating around the internet, but I will leave that between you and Mr Google.
I hate Apple as these days they seem to have out-Windowed Windows with their restrictive practices.
Cut the un-necessary Apple bashing please.
I could name you 101 restrictive Microsoft practices that beat any Apple ones you can name. It's a fact of life in the IT industry, all manufacturers impose restrictions in some form of another.
Fact is, that if you ploughed the same amount of time and money into R&D that Apple do, you too would want to ensure you see a return on your investment and maintain the quality of your product.