Liberalism is not inconsistent with regulation. Oligarchy introduces inefficiencies to the market. Liberal Democrats have been generally open to and supportive of regulations which oppose oligarchic monopolies, and mitigate externalities. They certainly have their flaws, too many to enumerate here, but they generally want the market to run as "purely" as possible, without the confounding effects of oligarchy. Oligarchy and monopolies upset the mechanisms of the market, and the liberals are the ones passing regulations to try to prevent that. This much is obvious by the existence of regulations, and the near absence of legislators to the left of liberals.