why is it that women tennis payers want equal prize money as men yet play fewer sets? Equality ?

This has been answered many times here. Only a few major tournaments have men playing best of 5 sets. Most are two out of three just like the women. The pay, is what the tournament organizers and television, are willing to pay for entertainment. The women's matches are entertaining, and draw a good audience. Sports do not just pay athletes for time spent. Some boxing matches last one round and the winner may receive millions. Even when the men play 3 out of 5, many matches last only three sets, like Nadal's match today. To sum it up, the women provide the public with entertainment, and are paid accordingly. There is also a question of whether the women could hold up for a series of 5 set matches. Many of the women players like Henin and Sharapova have battled injuries in the past year.

You are dealing with a group of highly competitive people in a society that uses $$ amounts as a scoring system for the relative value of the individual. They want to be first. They may settle for equal. But it is not in their nature to roll over and meekly accept anything less.

women just more money for less work