With an airline, everthing is about levels of service. You get a different level if you are in a different class and you get treated differently if you are a frequent customer. Sure, you get the loyalty cards (lots of places do that), but you also get many small priveleges with it. Being an "elite" member of an airline frequent flyer program means you get to board first, don't have to pay to check your bags, get upgraded as a priority and usually even get a dedicated phone line for customer service so you don't have to wait on hold for too long.

Despite all the other difficulties the airlines have, for a long time most have had the ability to set their best customers apart and treat them differently. They even give them luggage tags. What you are doing for your best customers?

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