Ethical behavior is incompatible with the pursuit of profit.
Nonsense. Pursuit of profit *can* lead to unethical behavior but it does not follow that pursuit of profit *must* lead to unethical behavior. Buying something and then selling it to someone else for a higher price has no component that is fundamentally unethical. If you have a good I need and I'm willing to pay a price for it (a price that is low enough that it does not cause me injury) then we both get something we want/need and both are better off. There is nothing unethical about that exchange.
I won't even get in to the question of what you consider unethical behavior or why. Ethics are societal conventions and standards which differ between people and groups, not immutable laws of the universe. Perhaps you do consider pursuit of profit to be unethical. That does not mean that the rest of society must consider it so.