It doesn't sit right with me that a government body has an ad account in a centralized for-profit service in the first place.

Even having a free account seems wrong to me. The European Commission could post news, updates on its work and polls on the official European Commission site. I don't think the government should favor corporate social media sites or have anything to do with them in the first place. If they feel like posting on their own site is not enough, why not use a free social media outlet? Something self-hosted, using ActivityPub, for example?