Liverbirdie
Ryder Cup Winner
I carry around 10 balls
To be fair on my course and and any other course I have played I would never have my bag that far away from me so this situation has never happened. I don't really see how walking back to your bag would back up a course.
If keeping 1 spare ball in your pocket is "bad karma" Surely keeping 10 spare in your bag magnifies it more.
Before playing a new course, do you check out the course guide to see if you will or may leave your bag far away? I would think not, people who don't carry a spare ball tend to never carry one.
If 2-3 and definitely 4 people have to walk back to bags 60 yards away to reload they will back it up.
Listen, as advised I didn't for years, but once pointed out to me I saw that you should, weighed it up and now always do.