Have you heard of it? Or are you aware of it? 80/20 rules, though not mathematically justified, is approximately an accurate description of the Business Rules and a reality that should not be ignored.
It states that 80% of your business comes from 20% of your total customers. Therefore, it is suggestive to focus yourself to these 20% of your customer rather the 80% of your non-profit customers.
It sounds very unconventional that you should ignore the possibilities of business from the 80% of other customers. But logically, it sounds perfect. Why spend money on such customers that brings no business? Instead, it is very reasonable to focus your business's attention to those who really care.
Also, this rule also extends itself to all the other domain like 80% of your complains comes from 20% of those customers which really do not bring any business. It all sounds so obvious and true.
Remember that any good rules always sounds obvious after it has been stated but it lies that it is operated or carried out properly.
There is also a saying that goes, Care about people that really cares about you.