If it is “just” to tax gasoline, as part of paying for roads, then there is nothing wrong with expecting electric car owners to pay some sort of fee that makes an average comparable payment to helping fund the roads that electric cars need as well.
While it might be Libertarian pure to complain about charging to fee to electric car owners, there is nothing honest about doing so. The “users pay” concept of most of the funding for roads should NOT exempt electric car owners.
Either get rid of the fuel taxes and fund roads some other way entirely, or be honest and admit electric car owners should not be “exempt”. The former is not practical so the latter ought to be admitted.