Unfortunately, most also protect milk processors from competition.
It became one of the largest milk processors and distributors in north east England.
As for the prices farmers get from milk processors, they have not changed much from the late 80's.
While the compact may require milk processors to pay more for milk, those increases will not necessarily be passed on to consumers, they say.
There are two classes of milk processors.
Now, the milk processors, who bottle milk, are changing their tactics.
This is the first time milk processors have done any advertising or promotion.
"The people who will determine whether consumers get hurt are the milk processors and the retailers."
It was not immediately known if the dairies supplied other milk processors.
The campaign comes at a particularly volatile time not only for milk processors, but also for all beverage manufacturers.