If using butter for bread I've just always kept it in room temp in a little sealable box, it doesn't go bad. But the butter we use here is always cultured, afaik butter in the us is not so I would assume it might go bad easier so your anxiety might be valid.

Same with eggs, they are not washed here so I just keep them on the counter.

Making cultured butter isn't terrible hard though, have made it a few times. Just takes time.

That's why you out water in the bottom, but also if you leave a stick of butter out for a few hours, unwrap it, and moosh it into the bell with the paper, it's easy to refill. It's lazier than getting butter out of the fridge.

If it was dangerous, people wouldn't do it with the frequency that they do.