It's easy to get an incorrect impression about an airline's customer base reading Flyertalk. Customers who get top status through cheap mileage runs are statistically insignificant -- and that would be an airline equivalent of the unprofitable little old ladies you mention.

Also, the airline's practice of selling miles for revenue doesn't have a casino equivalent.
So while better targeted offers and rewards could make a difference, I don't think it would make as much a difference as it does for Harrahs.

The real difference between success and failure at a casino comes from their ability to attract, and keep, high rollers. They do this with personal service, individually targeted. U.S. carriers have no clue how to apply this to the airline equivalent of high rollers -- frequent international passengers who pay full C/F fare. U.S. carriers also fail to sell to the person who has the authority to pay for the travel. For most business travel this is not the person who flies.