Right...the broken bellows seal has allowed dirt and grit to get onto the rod and wear the seal. An "ounce or two a week" is not normal. I've gone years and not added any PS fluid on any of my cars. I'm pretty sure you're stuck with a leak until the rack is replaced. I'm not sure if "leak preventive" PS fluids would help. I think they're designed to help more with leaky hoses or stationary fittings. Some say they help seals but I think that's when they have normal uniform wear. Yours have been scraped with dust and grit.