For them, the past has no meaning. They have absolutely no loyalty. They will shift suppliers of any product for a few pennies difference in price. Such buyers get little service. Service is not important to them.
Price is everything.
There is not much point in trying to win their loyalty, since they have none to win. They are not profitable customers, even though they do buy a lot of product, and represent an important segment of the market. The best thing that could happen to these transaction buyers would be for them to shift over to buying from your competition. Give them the competition's catalogs and phone numbers and hope they take the hint. Relationship Buyers are the people for which database marketing was invented.