Remember that most men who buy a kilt and sporran will only wear it a couple of times a year, so the wear on the kilt due to the chain will be negligible. People like Ham, who wear kilts every day, are much more likely to suffer wear.
I have only chains for my sporrans. I've checked them both for rough edges and couldn't find any. But because I find sporrans a bit of a nuisance, I only wear them occasionally so the risk of damage is minimal. I'm sporranless 95% of the time. I have a fanny pack which works better for casual if needed. Thanx to Graham for the idea.