i don't want to pee on anyone's chips, but i wouldn't want to be in the situation where n insurance assessor or accident investigator was looking at a car that i owned that was fitted with golf cart wheels
Would you feel the same way about a car you owned with split rims on it considering few of them go through any formal testing or approval process?
Split rims may be designed for cars but without any testing they could still the dangerous. Equally you could agrue that more 'golf cart' wheels are sold than split rims and as such there's a greater chance that their manufactures have put more time into making sure they're a strong and safe.
I'd also say that using a set of secondhand wheels with unknown history could be just as bad if not worse than a new set of 'golf cart' wheels as you wouldn't know if they'd been abused or if the had cracks waiting to blow the wheel apart.