CarRental8 Rip off rental agreement/rental car company even is you cancel 4 days ahead they charge..most zero with 48 hr notice Kona Hawaii

Tried to cancel my reservation 6 days ahead BEN told me I would be charged $42 for cancelling. 

i asked him if I picked it up but turned it in early would I be charged? Each time he spoke it was mas double talk. I finally just asked him to tell me yes or no to my questions.  That's how I finally got the above information. When I asked to talk to a supervisor because I felt this was an unethical business practice he said they would tell me the same. I asked why he was charging when most rental cars don't charge if you give 48 hours notice in advance. He said that his company had to pay the rental car people for my reserved car that they were already out the money???