I know why the Switch Pro controller is so expensive

[cannonballZ]

TomaTito said:

You have to be careful with usb type-c cables, bad ones are sold even on amazon.

http://www.androidpolice.com/2015/11/04/a-google-engineer-who-works-on-usb-type-c-products-is-reviewing-and-identifying-out-of-spec-potentially-dangerous-third-party-cables-and-adapters/

https://www.engadget.com/2016/08/16/usb-certified-chargers/

And the answer to your second question is already in the OP.

HD rumble may be the factor in the price. Even the Wii U pro controller comes with the charging cable and doesn't cost $70. I have never had to buy a charger cable seperate when purchasing a controller, have you?