According to your explanation - beefy men tend to not rinse soap properly...
Or other version - twinks do not shower enough or are too carefully with rinsing soap to get fungus infection...
Yes. It is well known that larger men are more likely to get fungal infections in the crotch area, simply because soap runs down their body and gets caught between their scrotum and upper thigh and needs more care to rinse away properly, especially when they only have a fixed shower nozzle.
The bigger the man, the larger his skin area, the more soap he uses, the more water he needs to rinse it off and therefore more likely to get fungal infections caused by residual alkalinity from soap.
1. don't use soap. Use pH neutral shower gel.
2. use a hand held shower to rinse everywhere properly.
3. soak feet in vinegar in water to neutralise alkalinity and prevent/cure fungal nail infection.