Why stock it at all then?
Is it sort of an "Eat at your own risk" arrangement for the few fisherman who do?
Years ago I used to use it just to practice my fly casting and though I never caught anything large there was the odd one that was around 5lbs.
I never, and wouldn't recommend eating anything I caught in there.
That being said,
fishing is more about the fishing than the eating anyway.
If you have to be the provider of food there are far better lakes to catch a meal than the locally stocked lakes which should be used for recreational/entertainment purposes only; taking a kid out, relaxing with a rod, practicing.... (IMO)
(but you might have to drive more than an hour).
I do enjoy fresh fish, but pellet fed fish taste like pellet fed fish and that taste doesn't really go away till after their, pen rounded fins grow back (and longer depending on the water they're in), and if they live in a shallow, muddy, goose/duck -poop filled pond that's what they'll taste like.