That's the basis of modern anti-trust: bigger companies (by market share) are held to a higher standard to prevent monopolies. Unregulated monopolies are even

That's the basis of modern anti-trust: bigger companies (by market share) are held to a higher standard to prevent monopolies. Unregulated monopolies are even more anti-competitive. And it's more competitive to only regulate potential monopolies than entire markets. It's the best of no perfect option.