Total non sequitur. Labor (and salaries) predate the existence of money, as well as capital investment.
Even under capitalism you can still volunteer, donate and create community orgs to build things, there's nothing stopping anyone.
Huh? You think that before investment, people didn't trade good and services of their own free will? You need to re-examine history. Commerce predates civilization.
If you think that slavery isn't needed under capitalism, how do you explain the extensive use of slavery under capitalism?
> Even under capitalism you can still volunteer, donate and create community orgs to build things
That's true, and is completely irrelevant to our conversation, because we're not discussing volunteering, we're talking about the distribution of profit. If there is no profit, there is nothing to distribute.
If someone wants to passively invest $3M into a new coffee shop and pay labor to work in it, banning it like you want to do will kill the economy and disadvantage the little guy.