Disclaimer: It might not actually be free.
“The bread is not charged for separately, but it isn’t free – the price is worked into the price of the other food sold. The bread is something inexpensive to provide that distracts the customer from the wait for service and their hunger, which is a compounding factor in dissatisfaction with the service (which may carry-over into the assessment of the food).”
There better be bread.
“Gosh, mostly customer expectations. If you charge for bread, or don’t have any, lots of customers think you’re gouging them.”
It is just like a tradition.
“A much simpler explanation: It’s customary. The lack would make patrons start out thinking the restaurant is bad / cheap / low-class / etc. Therefore, it’s a self-reinforcing phenomena.”
You need something to wipe your plate clean with.
“Let me introduce you to a little Italian tradition. It’s called fare la scarpetta.
You’re sat in a little trattoria, surrounded by the clattering of cutlery and the impassioned, melodic sound of Italian. Two raggazzi to the left of you are finishing their primi. One is devouring the remaining morsels of spaghetti alla puttanesca; the debris of olives and pomodori sauce splattering his shirt. The other is lapping up the last of his rigatoni al ragù: large cylinders of pasta oozing with dark, braised meat and flecks of parmesan.Each leans to the centre of the table and grabs a fistful of bread. Tearing it in half, they scrape the plate clean, bread soaking up the sauce and leaving a satisfyingly white plate beneath.
To fare la scarpetta is to ‘do the little shoe’; to wipe your plate clean with bread. Some say that the scarpetta is simply a metaphor; others that it originates from the poor cuisine of rural Tuscany, where people were so starved that they ate the soles of their shoes.
It might not explain why all restaurants offer bread… but in Italy it’s my favourite part of the meal!”