Brake Disc Pads problems of the 2017 Infiniti Q50

I purchased my 2017 Infiniti Q50 on October 06 2018 from carvana llc. The vehicle was used and had approximately 38k on the odometer. Within 2 weeks of owning the vehicle the rear brakes pads need to be replaced and the rotors needed to be resurfaced. This was expected due to the high mileage on a 1 year old vehicle. Then on January 11th 2019 I took my 2017 Infiniti Q50 in for its oil change at 43,000 miles with glendale Infiniti in glendale California. When the service was completed the service advisor had notified me that my rear brake pads where at 4/32's and would need to be replaced within 6,000 miles. I had the brake pads replaced with the factory recommended brake pads at firestone in alhambra on 6 October as stated above. I did take the car back to firestone in alhambra CA for squealing brakes mid December 2018 and it was also discovered that the front brake pads needed to be replaced along with the rotors needing to be resurfaced. The rear brakes now squeal and will need replacement for the 2nd time in less than 3 months. My car is used to drop my son off at daycare and my wife at work and then to pick them both up and some occasional travel and work for my part time job as a rideshare employee which total 859 miles in December. I have seen complaints from other owners about having the rear brake pads wear prematurely. I ask ed the service advisor with glendale Infiniti about it and he simply stated it is due to harsh braking. I responded with is that so because they where replaced with factory brake pads in October 2018. Since the find the squealing is intermittent when coming to a stop and my stopping distance has increased even at low speeds on city streets.