Afaik you can buy a truck as a dedicated transport for a unit of 30 boys, you just cant get them into it. So that part can actually work fairly well.I am not sure I would do that. You can only take the trukk as a dedicated transport and burna boyz can't get it. So, you will be disembarking something to that is small in unit size to make its way across the board.
Edit: Ignore the gray part, that will teach me not to double check before posting...
But as has been said before, burna boys are a tad to expensive (especially with their lack of armour save) to lug around in trukks.
Even if you go up against a horde army, the AV 10 of a trukk can be fairly easily breached by just firing a volley of bolter / shoota fire into it.