Generally (but not always) if a large bottle is marked with an LWS name, it's a company owned, not a customer owned, bottle and can't legally be sold by a third party. To complicate matters it varies by company.
One workaround I read about
: if you go to buy the guy's bottles, ask him where he refills them, or what company name is on the bottle's neck ring, and arrange to meet the guy at that company. Ask the company guy behind the counter if the bottles can be sold and make the transaction right there.
Edit: There's a youtube video here:
http://www.youtube.com/watch?v=ndGB-Ww47M4