The drills, impact driver, and charger that come with the black batteries are also cheaper. They are longer, less powerful, and probably cheapened in other ways to make them cheap enough to do black friday deals with them. Buy only the kits with the red batteries.
Example:
The PCCK600LB which comes with red batteries has the following features
330 Unit Watts out of power
Battery Fuel Gauge
Metal ratcheting chuck
7-3/4 length
40 Minute Quick Charger and battery maintainer
2 Speed gearbox with 0-400 RPM and 0-1,600 RPM
1.5 AH batteris
Magnetic Bit Holders
The PCC601LB which comes with the black batteries has the following
283 Unit Watts Out of power
No battery fuel gauge
Chuck is just listed as a keyless chuck, not a metal one
8-1/4 inch long (1/2 an inch longer than the other one)
The black slow charger (can take between 1.5 to 3 hours depending on the battery being used)
2 speed gearbox with 0-350 RPM and 0-1,500 RPM
As well as smaller batteries (1.3AH)
The drill kits that come with red batteries are way better.