> why can't we replace all our complaining factory workers and their wages/healthcare/retirement plans with these "creatures" and only pay them peanuts and banana's.

Automation would probably be cheaper, more consistent, and more effective.

Biology wasn't designed for production line work. Humans are really bad at it. Engineered primates might be better at it because they'd be engineered not to get bored or frustrated, but they'd still be a fraction of a % as efficient as a machine with 100 arms and conveyor belts.