Le mot du jour : “Ça ne mange pas de pain !”
That expression, still in use today, goes back to the 17th century. Its word-for-word translation would be “that doesn’t eat bread” and its meaning is along the lines of “it’s not big deal” or “there is no harm in it”. It all goes back to the time when bread was the main food and the main way to assess the value of things. So if something had no negative impact on your capacity to buy bread, then you could go for it, there was no harm done. It wouldn’t eat out your bread’s allowance.
So you could say today “Je vais juste regarder le prix de ces nouvelles chaussures, ça ne mange pas de pain !” (“I’m just going to check out the price of these new shoes, there is no harm in that”)