Cyclists don't get the point about Road Tax.
It's not that Road Tax doesn't exist (since Churchill abolished hypothecated 'road tax').
It's not that Roads are paid out of general taxation and most people are tax payers, some even have cars that require VED anyway.
Motorists get annoyed about cyclists for 'not paying road tax' because, unlike the majority of motorists, cyclists don't have to pay any special vehicle related money (not matter what it's called, or if they'd be exempt anyway) towards the general taxation pot in order to 'use the roads'.
No, wait a minute, that's not trolling is it, that's actually the truth...