The mobs doesn't ride the minecarts and boats, it is harder now for a player like me to catch zombie villagers when they won't ride the boat under the shade, if only leads are applicable to them, I would... but really it won't.

It is not much difficult to transfer animals like sheeps and cows, and other friendly animals. But when it comes to transporting villagers, despite their behavoir, it will be a big problem for me.