"The only people who call customers 'users' are drug dealers and software companies."

'User' has been a term in computing for decades before the current Cloud Services fad ( hence uid ).

One uses a hammer, one uses a microwave, one uses a computer, one uses a word processor. Nothing negative towards the user, they're being productive with the product.

If anything it's derogatory in the other direction, towards the manufacturer, reducing the fruits of their labour to that of a simple tool.