Food animals Accommodation Crickets?

Just now on my way home, I found a package of these feeders at the dumpster. Most of them were already dead, except for four. I just couldn't bring myself to leave them there. But I also wasn't sure if I was allowed to release them like that, so I've put them in a temporary home. Can I release them, or would that be stupid? I've put in some grass, water, a little cucumber, some oatmeal, and a branch like half a coconut shell. I wanted to make it cozy, but unfortunately I didn't have anything big enough.

I've only had mealworms so far. I might keep them as small pets, but honestly, I have no experience with such crickets.