At a tournament in Michigan a long time ago I met Mark "lizard lawyer" Ellis. I helped get one of his Discraft Crush that went into the water for him. When I grabbed the disc I noticed some black sticky stuff smeared on the underside of the disc. Talked about it with another player and was told he regularly uses the pine tar type stuff, and they try not to touch his discs lol.
I know he threw alot of Forehands so it makes sense. I have had a bunch of Forehands slip out early when my hands were sweaty. I never thought of it as cheating and still don't.
I have seen Ezra use those Friction gloves quite a bit in practice rounds. I assume to prevent his fingers getting torn up. Ball golfers wear a glove for grip...football receivers...baseball batters...
Since our arms/hands/fingers are the Levers that propell the disc, I don't see a problem with adding grip to your hands. Some will end up on your disc inevitably.
I don't see it as an advantage. If anything it will make your grip inconsistent for the softer shots and putting. Constantly adding on goo for driving and taking it off for putting.
I think the best combo would be the Friction glove for driving and birdie bag for approach/putts. Still alot to fiddle with during a round.