I'm 100% the opposite. It's wrong for one group to expect preferred stock for their capital contributions, while they ask the usually less experienced CEO to make a tacit capital contribution (lower than market salary) and then on top to ask them to put cash in that won't be given the same terms -- nah.
Now, if the founder capital went in pre-round, and a round was raised, I'm with you -- that's fine - and between the founders at that point; they got paid in equity valuation. But otherwise; nope.
We're talking about arrangements between founders, not arrangements between operators and investors. Investors don't ask you to put up cash; that is literally the opposite of what they do.