we usually consider the person making the leap a (misguided) bleeding-heart liberal, not a promoter of "evil behaviors, up to and including armed robbery".

Really? How are government tax collectors any different than armed robbers, on the relevant dimensions? After all, governments love to trot out "giving money to the poor" as a rationale for taking your money, don't they?

(And no, the fact that the requirement to pay taxes is imposed by statute, or that the IRS labels your compliance with their policies as "voluntary" are not relevant dimensions)