Do free-trade economies typically offer any protection for domestic markets? The aimed-for outcome of the protectionist could be said to be the shielding of domestic markets from competition with an "unfair" advantage. For example, an emerging economy might have non-existent workers' rights enabling lower production cost.

However, discussions surrounding naive protectionist policies typically descend into "define a biscuit" type arguments. In short: the difficulty in defining the boundaries of tariffs quickly turns arguments to farce.

But there must be other, better ways to achieve the desired outcome. I have read that in the early 2000s Germany "protected" its intra-EU car sales by ensuring EU emissions regulations were closely aligned with the emissions of their own diesel engine technology making market entry by (for example) American cars with big petrol engines more difficult. Whether this is apochryphal or not, the point remains.

Do free-trade economies typically endeavour to protect themselves in ANY way, or does "free mean free" in the minds of these legislatures?
I think the (or at least, a) relevant concept is that of non-tariff barriers to trade. Wikipedia has a nice summary.

Let me quote a couple of sections from the article:


  Non-tariff barriers to trade (NTBs) or sometimes called "Non-Tariff Measures (NTMs)" are trade barriers that restrict imports or exports of goods or services through mechanisms other than the simple imposition of tariffs. The SADC says, "a Non-Tariff Barrier is any obstacle to international trade that is not an import or export duty. They may take the form of import quotas, subsidies, customs delays, technical barriers, or other systems preventing or impeding trade." According to the World Trade Organisation, non-tariff barriers to trade include import licensing, rules for valuation of goods at customs, pre-shipment inspections, rules of origin ('made in'), and trade prepared investment measures.


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  According to statements made at United Nations Conference on Trade and Development (UNCTAD, 2005), the use of NTBs, based on the amount and control of price levels has decreased significantly from 45% in 1994 to 15% in 2004, while use of other NTBs increased from 55% in 1994 to 85% in 2004. [...] The need to protect sensitive to import industries, as well as a wide range of trade restrictions, available to the governments of industrialized countries, forcing them to resort to use the NTB, and putting serious obstacles to international trade and world economic growth. Thus, NTBs can be referred as a new of protection which has replaced tariffs as an old form of protection.


So regulatory and similar barriers to trade have become widespread—often as a way to circumvent restrictions on protectionism.