I don’t think it’s quite that simple, Sky can only set their prices based on the market (supply & demand etc.) and then once they’ve earnt their profit, the can choose to donate some of it to charity, rather than giving it to shareholders / reinvesting it. Obviously the cycling team is a marketing cost.
But I agree that it would be difficult to find a cause which all Monzo users would agree on. So my preference is for Monzo to make it easy for users to give to causes that they’re passionate about, through features / integrations like this -