My P model doesn't have the 3100 MGTOW STC and has 1134 lbs of useful load, 654 lbs at full fuel with long range (79 gallon) bladder tanks.
Four "standard" 175 lb humans is already almost 50 lbs over my full fuel weight, plus whatever four sets of golf clubs weigh. And most 'Merican humans aren't FAA standard sized these days.
Now if you leave some fuel off and make some assumptions like "most folks won't go more than three hours without needing to pee", you can put four hours of fuel on board and get the remaining useful load to 822 lbs and have VFR day reserves plus another 1/2 hour worth of fuel for "stupidity"... winds aloft changes, runway closed because someone munched an airplane on it, whatever.
If your buddy, his wife, and the couple he wants to take golfing are skinny people and they only take the clubs they need to survive, maybe then.
The 3100 MGTOW STC has a distinct problem from a planning perspective -- you still have to fly off enough fuel to get to 2950 for landing. 25 gallons, which is more than two hours of flight, if you're maxed out. If you climb high, almost 2.5 hours, since fuel burn drops to about 11 GPH up higher. Which means your golf course airport can't be within 250 nm or so. Short hops, the MGTOW STC doesn't do you much good.