There are a few reasons... There are four zombies that cause bonus attacks: trickster, electrician, neutron imp, and gadget scientist. There are two zombie tricks: lurch for lunch, and the super, carried away.
This is an important distinction because zombies have both bonus attacks and frenzy. Two different effects.
Now, keeping that in mind. Mirror nut has an ability that activates under the condition of a nut being damaged. Wing nut, much like bonus track Buckethead, has the effect active as long as the card is on the board. So, if I place a bananasaurus in the lane with bonus track and fertilize him to a 6/6, he'll kill bonus track and, since bonus is no longer on the board, do his bonus attack. Same principle.
So even if frenzy is counted as a bonus, once the card is off the board, all bets are off. It's all in the wording of the description. Is it a passive effect s long as cards are on the board, or a conditional that requires an action to be fulfilled?
