system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are recycling places such sticklers about items being washed out?

If a bottle or can has a label glued to it or paint on it, how is that so different from a bit of food?
gpt
Rats and other vermin are hard to deal with.  Dump a bunch of oily, dirty old food tins and soda bottles with sugary residue into a big pile, you're getting mice, rats, and vermin of all sorts.  They'll travel with the cans and bottles down the sorting lines, into the shredders, etc., messing up the equipment and the workers.  Labels and paint can be removed by passing the shredded materials through a chemical bath or sprayer.  Food particles have to be washed out (along with the vermin).