Question on future trading - overnight fees or not?

Hi traders, I have a question on future trading. On my CFD account I see overnight fees when I trade spot CFD but no overnight fees when I trade future based CFD s. The CFD broker takes the future's overnight margin for defining the margin for the CFD, the future broker gives me a daytime margin which is 5-25% of the overnight margin depending on the commoditiy future (or index future). Even with the overnight margin I efffectively have a 1x10 leverage and it is 10% of the lot's value. **So my question is - who does effectively lends the 90% of the money? Are there overnight fees later hidden in spreads?** e.g. there is a contract XYZH25 (March 25 delivery for something XYZ) where the lot costs 100.000$ but the overnight margin is 10.000$. Who lends the 90%? Or is this 10x leverage effect coming from a "downpayment" of 10% and the remaining 90% are paid when the contract is settled? The trade is always over the lot's value not the 10% of the lot's value I must provide as overnight margin or the 2,5% which I have to provide as the brokers daytime margin. The brokerage said the overnight margin is demanded by the exchange but the daytime margin is demanded by the brokerage.