Hey Porky. I know about half of the strongest guys at my gym train with their pinkies on the ring, they are football players. The ones I know that train for strongman competitions put their fingers in the same place as you do. Why do you think there is such a difference? Like I assume its to prevent shoulder injury, but is that it? Sorry, though I'm seasoned in the weight room, I've had the exact same grip since I was in high school, and just recently began experimenting with narrower/neutral grips to help.
It could be any number of things tanker.... sometimes strong is strong and has nothing to do with set up or grip. If I go to a commercial gym and start benching every week with my hands touching in the middle of the bar, I'd put up way less weight than I could with a good grip, maybe low 400's instead of mid 500's raw.... but I'll bet that after a few weeks I'd start seeing other guys doing that as well. My strength has nothing to do with the grip, I just came in there stronger... that could be the case with the guys in your gym, or it could be that the narrow pressing carries over better for football so their coach has them doing that.
Lifting the most weight is about shortening the range of motion as much as you can without putting yourself in a bad position to push. For a short armed guy gripping as wide as I do could be a terrible position to push, but for a guy with ape arms my grip might still feel narrow. The strongman guys are likely training for overhead pressing where you'd use a wider grip to favor the stronger triceps and take some work off of the delts while shortening the range of motion.
Obviously grip will vary depending on how long your arms are, how wide your shoulders are, and what you are trying to do. If you want to hammer triceps then by all means grip narrow..... but most top benchers will press ( out of their bench shirts) with 1st or 2nd fingers on the rings. I'm not just talking about the guys putting up 400 at a golds gym either. I make the trip once a month to lift with a guy who is one of the best pressers in the world. That whole crew is pushng weights in the 800-1050 range in the gym. Even my regular crew that I train with the other 3 weeks a month are all in the 7's and 8's. Everyone has a similar grip, so that's what I use.
So, grip is pretty similar for all for all of the powerlifters ( above 200lbs.... the light guys might be narrower)
As for shoulder injury, this has way less to do with grip and way more to do with set up. Guys who lay flat on the bench get torn up shoulders way faster than guys with good set ups. I've already written a freakin' novel here.... so, in a nut shell... I'm talking about tucking the shoulders back hard, really squeezing the scapulae together. Then setting up on the bench with your back arched. When I'm on a good, grippy bench and set up to lift big only my traps and butt will be on the bench ( and my upper shoulders obviously).... tuck your shoulders back hard, dig your traps in to the pad, then drive your feet away from the bar hard to push your butt up toward your head, forcing your belly up and your back to arch ( usually painfully LOL)