Clothing racks are quite useful but I think you will always find the cheap ones from the supermarkets are not up to the task of much more than lightweight clothing items and occasional use. For a number of heavy kilts, jackets and coats you might want to consider a heavyweight commercial garment rack as used in showrooms and factories. They may cost more but should also last decades of hard use and probably never need replacement. Designed to reliably accept large heavy loads they are unscathed under weights where even most home closet bars will bend or even break. Since the cost of a single failure in a commercial setting can be significant they are typically made to be bomb proof. Mine is made of heavy chromed tubular steel and has wheels good enough to push a full rack with 100s of kg of clothings down the road.

A quick search of the U.S. market for racks that could fit the bill turned these up:
http://www.aitequipment.com/cgi-bin/...r2.htm&0=EZ500
and
http://www.garmentrack.com/zgarmentrack.html