Best practice on businesses name-squatting on social media

I'm running a startup that's pretty active on Twitter and LinkedIn. We've got Instagram and Facebook accounts to hold onto the name, but our target audience don't seem hugely active on there, so we rarely post there.

I've been thinking about what to do with the IG and FB accounts recently, and I'm not too sure. It feels wrong to hold onto the names just because we might one day use them, but it also seems to make sense from a brand perspective.

My question, I suppose, is what do you think is best practice on this front and why?