Return policy is horrible

I went to the pep home in chatsworth to do a return on the 8 March 26, it was a bit early like 5 minutes after opening. I purchased a few items the previous week and wanted to return two items as they did not fit. I was told by the manager that they could not assist me until they do a cash sale to the value of my return....so are we expected to stand in the store and wait until they have done enough sales ? I understand if this is there rule but why do they state it on the windows. Now I have to travel back to get the return done which is an inconvenience to me.