Hi Folks,
I never worked with those amplifiers, just guessing: this is related to the usage of bridge mode.
In bridge mode, the loudspeaker is connected to the positive output pin of the left channel and the negative output pin of the right channel.
If both negative amp pins would be grounded, bridge mode would have to be implemented differently (connecting the loudspeaker between the two positive pins and inverting the signal to the right channel internally).
The positive pin of the right amp being grounded rather then the negative pin is just a matter of circuit design...
Best regards
Crestronfreak55
