Heater ground connection

[ChickenPinz]

In debugging a parasitic drain on the battery when the master switch is off, I found that there was a heater ground connection onto the battery relay connection with a spade-connector Y adapter. Does anyone know why this might be the design rather than a chassis ground connection? It seems like it might bypass the master switch, maybe in an effort to allow heater use with the vehicle turned off.

Is this the normal way the heater ground is connected?