Do particular zombies have any impact on the chance to drop items/coins?

I have asked about the chances of an item being dropped in PvZ1 before, but i was wondering, do certain types of zombies have an effect on this?

I was watching a speedrun of the game, and when they reached the Bobsled Bonanza minigame, the bobsled zombies really came out in force!

So I was wondering, is this a potential farming technique for money or items? Or do certain Zombies (like the Bobsled Zombies) have less/no chance to drop items?