We hear of similar problems all over, but there are many causes. I haven't heard of any class actions against copper yet, although individual suits are often brought against contractors for faulty installations and water companies for bad water. You could talk to a local attorney to see if you can find someone to blame; a quick Lexis search will turn up any applicable case law.
However, you'd probably spend less money just fixing it. Cost around here to re-plumb a 3/2 on-slab home is typically around $3K. Most use CPVC, but PEX is becoming more popular. Depends on your individual situation.
After becoming aware of an under-slab hot water leak, I re-plumbed my house myself for a few hundred dollars in materials, and a lot of quality time fighting off the dust, fiberglass, bugs and snakes in the attic. Electric bill dropped by about $40/month, so I'm happy.
I'm not sure I'd do the job for someone else for $3K, though.