After I had fiber installed at my grandmother's apartment in Shanghai, I found a backdoor in router that China Telecom provided. It was similar with Verizon in the US where they have your wifi password and remote access for various things. Then there was Cablevision that turned every router that they provided to people in my area into an access point without permission. Beyond having creepy backdoors, ISP provided routers are junk. There is no good reason to use them.
As for Ubiquiti being consumer grade, it is like an Intel Xeon E3. It is the same chip that is used in consumer stuff with enhancements for reliability. For instance, Ubiquiti equipment supports grounding via STP Ethernet. It generally supports some variant of PoE and is meant to be mounted on walls and ceilings. There are even outdoor models. It also does not require a reboot on every change. In addition, there is a team of engineers working on making the firmware better and their customers are able to report problems to them. Then there are firmware features like VLANs, policy based routing, BGP, ping watch dogs and other things not found in stock firmware of consumer grade equipment.