This may sound weird too, but in the spirit of helpfulness...
I have a few light color non-Chanel bags and I have had color transfer if I carry it in a way that makes it rub against one spot repeatedly as I walk. Usually it's when I wear the strap long and it is resting/rubbing on my hip if that makes sense.
My trick to prevent it is to slip a small silky scarf into the back pocket of the bag (mine has one) and let it drape over the leather. It usually adequately covers the primary rubbing spot and if I fold it right you can't even see it from the front. Mind you, this is only an issue for me with very dark, indigo kind of denim (which I wear a lot).
I have a gorgeous beige claire jumbo w/GH and have not experienced any color transfer to date.
To avoid it, I do not use this bag when I am wearing jeans or anything dark or new. I know that sounds a bit crazy but I only wear it with light coloring clothing that has been laundered and is safe from bleeding. Should something happen, I think Meltonian will help to remove dye and is good for conditioning the leather in general. I am sure others will chime in with their experiences and knowlege though.