Binance Funding Rate

Hello,

I read the documentation on the funding rates for futures. https://www.binance.com/en/support/faq/360033525031

However, I don't understand why there is an interest rate component.

Binance uses a flat Interest Rate, with the assumption that holding cash equivalent returns a higher interest than the BTC equivalent. The difference is stipulated to be 0.03% per day by default (0.01% per funding interval since funding occurs every 8 hours) and may change depending on market conditions, such as the Federal Funds Rate.

If I am trading a future contract either on margin or fully funded why should pay an interest rate given this is a derivative? If I am short the contract, should I receive this interest rate?