Yeah, the domestic coach product on the legacy carriers isn't good for non-elites, but it's still materially better than what Frontier is offering. Frontier seats really are bad. But it's all a question of what it's worth to fly something a bit better. My personal strategy is to go with the legacy carriers when they match (or get close to) the Frontier and Spirit fares. But if Frontier is half the price, I'd fly Frontier.