Legally, it is a use tax, not a "sales tax." Your reasoning is flawed, and therefore your conclusion is unpersuasive.
That is a flaw in word usage, not reasoning. Just trying to keep it simpler; the use tax is, for every state I’ve studied, defined with the sales tax, and implemented congruently. The distinction is meaningless to the argument, and therefore your objection is not meaningful; I do however thank you for clarifying the term, as I could have mentioned it.