Why did french economic philosophers of the 18th century want free trade?

Despite bread prices being ridiculously high french economic philosophers sought to simultaneously respect every ones property. they opposed maximums on bread because that would force the bread sellers to sell the bread lower than the bread actually cost to buy for the bread seller. should these laws have been implemented one of two things must have happened. 1) the bread sellers go out of business or 2) the government makes up the difference to bread sellers which would have launched France further into debt. i hope i did a satisfactory job of answering and if you have any feedback regarding said answer i'd love to hear it.

He would most likely post his laws in the city market