Economically there is no good reason to distinguish between these two cases. So you are saying because anything that could be rented can also be owned, the gov

Economically there is no good reason to distinguish between these two cases. So you are saying because anything that could be rented can also be owned, the government should get to tax it as if you rented it? This applies to all items that can possibly be sold and creates interesting areas for where something might be illegal but free to give and which still has a market value on the black market, of which income tax is still expect. For example, if you two people have sex, they both need to pay the tax a prostitute would've earned. It also makes every action taxable... even if all you do is clean your room, you aren't paying for someone else to clean your room and thus owe tax.