Your idea about the sheepskin seat belt pad over the cart bag strap is a good one. I have had many Titleist cart bags and never had a problem with damage from the strap, but my 2017 Titleist Mid Staff got pretty chafed up, and did so quite quickly. I have since gotten in the practice of not cranking the strap very tight and I try to remember to stick an extra towel behind the bag where it hits up against the back of the cart basket/cubby/storage area. After 200 plus rounds on a cart with this bag, it is still in decent shape, but not perfect. Most damage was done to it before I really noticed the problem, which was in the first month or two of ownership.

OP, I know what you mean about straps possibly ruining a staff bag.

I've had 2 problems in the past. I had a Scratch Golf staff bag when on the cart the bag rubs up against basket behind the seat and basically wear a whole in my bag, but the strap did not cause any problems on that bag

The last couple years (not 2017) I had the previous gen staff, the 915 staff bag. But the straps rubbed against the big white sides with the Titleist logo and did end up leaving black marks on those parts of the bag.

So all I did was hang towel up against basket and against the bag and between my bag. It helped with...
1) keeping the backside from constantly rubbing against the basket
2) helped protect the sides from the straps
3) it gave me an extra towel incase I need it to clean grips and leave my bag towel to cleaning heads and not getting sand dirt and mud on my grips.

So the pics are of what the basket did to Scratch bag (just under "S" it wore a hole) and how I set it up now with a towel. I just tucked it in the club holes so it'd stay for pics but the straps hold it in place, and my dogs Divot (possibly the best golf name for a dog but I'm bias) and Elliot snuck in the pic as well

I think this will help protect any bag with adding stuff to the actual material to protect it.