I will change a few words in your question to make some senses. >>...A convenience store owns the place. They have the legal right to decided who is and who is

I will change a few words in your question to make some senses. >>...A convenience store owns the place. They have the legal right to decided who is and who is not allowed to buy (candy, alcohol, cigarettes...). They sold to that particular client, the client paid it, and then later the store revoked the sell. When the client refuses to return the item at that point, doesn't he become a theft? <<. I am sorry to say the client is not trespassing since he already paid, he got this seat number and is already seated in the plane. The trespassers were the 4 employers that the crew has decided to kick the 4 others clients. That is called favoritism.