When you say 'that hard to clean,' I'm shocked you even have to ask. Just think about all the little grooves and edges that need a tiny brush and so much time. Take a cheese grater, for example, the bits get stuck and you scrub forever. I once spent an hour on one part and still didn't get it all. It's not just wiping it down, it's a whole project. So yeah, they really are that hard.
Ugh, that reminds me of my garlic press. The tiny holes get clogged with paste and it's impossible. I basically just rinse it and hope for the best now. Some tools are just not worth the fight.