So what is consensus on client libraries like this? Personally, I'd rather just use my own calls. Aren't most RESTful APIs simple enough not to need such librar

So what is consensus on client libraries like this? Personally, I'd rather just use my own calls. Aren't most RESTful APIs simple enough not to need such libraries? And if they're not, it's a design failure? But then you have companies like Braintree that only supports its libraries?