Answered by Shaykh Amjad Rasheed
A Shafi’i student of knowledge told me that, when ordering food, there is no contract between me and the restaurant and that I’m not morally required to pay for it; if I pay anything for it, it is purely voluntary, and if I leave without paying, there is no sin involved. Is this true? If so, why?

Our imams mention the ruling on this matter in the chapter on hiring and renting (Ar. ijara), as is found in Imam Nawawi’s Minhaj:
If one gives his garment to a bleacher to bleach or a tailor to sew and he does so without mentioning payment, none is due to him. It is also said [1] that he is due payment. It is also said that if he is known for that profession, then payment is due, otherwise it isn’t, and perhaps this is most preferable.
Thus, he mentions three opinions. The issue is presented, as found in the examples of the Minhaj, in the context of offering services. So is offering goods, such as food, like this? The relied upon position, as explicitly stated by Ibn `Imad, is that food is like a service, so there are three positions regarding it. Of these, the reliable one is that he gets no compensation. For it is transmitted that he [m: (i.e., Ibn `Imad)] said that an example of this i.e., that work done without specifying compensation is not due any is like a person who drops by a chef and tells him, “feed me a pound of meat”, and he does, because [m: (in the example, the chef)] didn’t mention the price. The mentioning of price is of consequence in sale, whether valid or invalid. A similar discussion is explicitly presented by Al-Khatib Al-Shirbini in Al-Mughni and by Ibn Al-Muqri in Al-Rawdh.
Although the above is the relied upon position of the school, the third opinion that rules according to what common norms is, as you know, a strong opinion. Al-Nawawi says, regarding it, “perhaps it is most preferable”; i.e. in terms of weighing the evidence, as is in the Tuhfa. Ibn Hajar says, “because of its clarity, for it is a common norm and often takes the place of speech. Thus, [m: this opinion] has been transmitted by most and many have ruled according to it.”
The above opinion of Ibn `Imad’s was transmitted by the erudite scholar Ali Al-Shabramallisi, who found it problematic, and followed up by saying:
In my opinion, it is possible that it is conditioned by the chef actually having sought compensation by handing over [m: the meat], particularly when the circumstantial evidence indicates this. So, what is most likely is that he is due compensation and is believed regarding the amount spent [m: for the meat], for he is at a loss, and his word is what counts.
In my opinion, what Al-Shabramallisi says corresponds to the third opinion that takes common norms into consideration. As the erudite scholar, Al-Shabramallisi, points out in the supercommentaries of the Tuhfa, it does not correspond to the relied upon position. Nonetheless, this opinion (i.e., that takes common norms into consideration) will guarantee that parties avoid conflicts. For no two people differ that one who takes on the cost of renting a shop and prepares it with all the necessities of a restaurant and hires employees to work there and serve customers, that such a person seeks compensation for his work, service, and the costs of the food and the like that are served. If the mention of compensation or price doesn’t precede this (i.e., the service and food), it is because of what everyone knows: namely, that the very setting frees one of the need to mention price and compensation. If the one who ate then gets up and refuses to pay the price and compensation, he is without doubt entering into an argument that will most likely prove excessive such that those with self-respect would rush to pay the compensation and price for whatever was served to them rather than get into such an argument.
And Allah knows best.
Notes
[m:
[1] The use of phrases like, “it is said”, in classical Islamic texts indicates that the author is mentioning an position that is not relied upon.
]
-Amjad Rasheed
(Translated by Sidi Moustafa Mounir Elqabbany)