The main profit in free trade is taken by foreign companies. But sometimes, because of them the rates of the product by the domestic sellers increases or in other words it increases the rates of local or domestic producers and it is just because that after this competition the domestic seller or producer, produces and sells lesser products in the market but on high price. It is also not beneficial for the country because after this the government can lose a lot of money. In this type of situation the tariffs play an important role. When a government imposes tariffs or taxes it at a certain amount ends up the competition in the market. In other words if there is a bit tax on the imported goods then the cost of the product will be high and it will be as normally demanded as the other domestic products.
It is sometimes good for the foreign companies because they can also dump their normal quality goods to the host country and it can generate a well amount of revenue for them. If foreign companies making a place in the market of the host country then it is also beneficial for the host country because it will also generate employment for the people of that country and produce goods on lower cost and sell it on a bit much that the domestic or sometimes they do the opposite to fail out the domestic sellers products. Sometimes it creates the monopoly for the product of a certain company. But it helps the economy of the host country also and just because of this the domestic companies also start to sell their products in the foreign market to gain more profit.