It is more because of those customers are high paying. It is normal for businesses to want to make high paying customers feel good because they pay very high.There are so many reasons for this, it could be because they are high paying customers. In other cases it could be because the customer is extremely loyal.
Every business person has customers that they give preferential treatment to. And it is always because of a reason best known to the business.I do not think a business is loyal to any particular person, I believe it offers same kind of treatment to all