Lodi - No, they're after already composting material. But it is thought that they eat microbes. I kind of doubt the parasites would outlive an active bin, as it's inhabited by an amazing variety of creatures all busy doing their jobs, such as predation. Worms are quite vulnerable to worming medicines, however - so be cautious when sourcing manures. ( but I am not a soil scientist - check with one if you feel you're at some risk)
Rickster - your holes might be kinda big, allowing material to dribble out. I do 1/4" small at 4-6" intervals along the sides in 2 or three rows The worms, being photo-phobic will only try to leave if they feel they have to because their "bedding" is too hot or inhospitable. There is heat from the first stages of composting and the worms must have older material to escape to. This is why I use a bin for fresh stuff, which becomes great for worms in about a week (at mid-range temps) and I can then add to my worm bin.
Verimicomposting is a great relationship. Look at them often, see what kind of material they are busiest in.
They love.. watermelon, squash, oatmeal and all kinds of surprising things like stems, which they hollow out and they then curiously, congregate in an orgy of numbers. Little worm churches ? Maybe they're grateful too.
enjoy
here's a quote- " I've woken myself up laughing" - an anon friend