I am not saying the examples you give of certain liabilities as a form of funding are wrong - I agree with them.
But your reduction of ALL liabilities to funding is incomplete, as can be seen with taxes.
Taxes owed are a liability on a company's balance sheet and they do not represent any source of funding.
They do represent, like all other liabilities, a future financial obligation towards another entity, in this case the government.
This is what all liabilities have in common.