That (to my mind) stupid, shortsighted, anti-green, dangerous, economically ruinous and unenforceable idea was floated some time ago in Vermont. It was, of course, as you'd expect, the proposal of a conservative legislator who was in the habit of ranting about too much government and too many regulations, but he saw no problem with the idea of instituting a new set of government regulations, penalties, legal hurdles, and administrative bureaucracy, on the grounds that bicycles were slowing him down when he was driving on his urgent business and "freeloading" the scenery! Yes that was actually one of his arguments.
The proposal was to require all bicyclists above the age of 16 to register every bike they owned, and to be licensed. Now, among other things, this would presumably give the police a right to stop, frisk and question any rider they thought might be in violation, including teenagers who would not be, and would, in this instance, have required out of state cyclists in this tourist-dependent state, to register before they could ride on our roads, meaning among other things that no out of state tourist could ride into Vermont during hours in which the bureaucracy was not open. And, of course, the exemption for kids amplifies the idea that bicycles are for kids, not adults. Aside from all the other silly consequences of such a bill, it would almost certainly require that every highway entering the state from any other state or province would have to have a prominent sign announcing that this rule, unique in the world, applied, and providing information on how to cope with it. It would also, i the case of Vermont, have required that many of the State's own publications, many of which promote cycling as a tourist activity, be rewritten, and provisions made for out of state tourists not only to be accomodated, but perhaps even to obtain licenses before arriving, a new bureaucracy which would, in turn, have to be publicized throughout the world.
The stupidities of such a scheme are abundant. Now of course I speak here as an advocate of bicycle riding, and a former (alas, only former after my encounter with a car) road cyclist, but if one proposes such things, one must contend with many complications, including the almost automatic inherent added energy cost. No doubt the added revenue would look good on the balance sheet if one fails to count the hidden and not so hidden costs to the population. How many heart attacks do you suppose it would take to offset? How many lawsuits for the deaths or traumas of vulnerable citizens would it take to offset? Not many, I surmise.
I can understand, even if I don't much like, the idea of an excise tax on new bicycle sales, but that is a far far different thing from taxing or regulating the use of bicycles. One idea is maybe a bit misguided, while the other is extremely bad and worse if you take the time to think about it with even a smidgen of actual imagination to offset the automatic partisan spin.