I wasn't even sarcastic. Once you accept some tax/fee/charge in principle, there is no limit on how high and haw far it can go.
Once you decide that income tax is moral/acceptable, nothing prevents the gov. from making it 100%. The only limit you could maintain is a 0, like in abolish it, make it unconstitutional (or rather obey the constitution since Amendment 16 was never properly ratified to begin with).
Same with Captain' statement. Once you accept a notion that "ability to pay" is a determinant of a price of death, the same argument holds for any event (marriage, moving to a new house, Birthday), activity (driver's license), or a purchase (bread, car, house, a yacht or even a corporation).
You want to buy Microsoft? The price for Bill Gates is $40,000,000,000, but Joe Blow on wellfare can buy it for $14.75.