Yes, technically, they are harmless. They don’t bite. They don’t carry diseases. They don’t eat your wooden furniture (they eat rotten wood, which is different).
But let me tell you about the psychological terror. That feeling when you grab a can of beans and a woodlouse stares back at you from the label? That’s not harmless. That’s a public health crisis for my sanity.
Also, they are surprisingly fast when they want to be. One minute they are playing dead. The next minute they are doing a hundred-yard dash under your stove. Rude.
Final Thoughts (From a Fellow Sufferer)
Look, you can’t kill them all. I tried. I put down diatomaceous earth. I used sticky traps. I even considered training a spider to be a bodyguard. But no.
The best you can do is make your house less inviting. Keep it dry. Fix the leaks. Take out the rotting cardboard boxes. And accept that you will occasionally find a tiny crustacean-tank having a morning commute across your toothbrush.
Just remember: they are more scared of you than you are of them. Unless you find one in your bed. Then all bets are off. Then you burn the whole place down.