Yes, the key is it's unlawful. You had asserted that the difference between theft and taxation was that "Taxation is not theft in so far as it is a means to pay for services which people may be able to avail themselves of."(*) I provided an example of which you agree is theft, which also paid for services which people may be able to avail themselves of. I did this as a way of showing you that what the seized wealth provided is not the distinction between taxation and theft. The distinction is whether the law allowed them to be seized.(*)
If someone took your car or home and sold it, illegally -- it would be theft. If someone took your car or home and sold it, legally -- it could be a tax. Whether the money from the sale was used to build a well or just handed to J.P. Morgan... well, the fed has done both (and worse). They still call it a tax.