I run a laundry service for restaurants and hotels. We supply them with table napkins, table cloths, chefs wear, bed linen, towels and so forth. My question is this:Am I able to supply a pub? The reason I ask this is that I view a restaurant as a place to primarily eat in. Even though they sell alcohol I see this as being secondary to their main purpose. On the other hand I view a pub as a place to primarily buy and drink alcohol. Even though the pub sells food I see it as a by product and not their main purpose for business.Would there be any haram involved in servicing a pub?In order to understand the Islamic perspective, theoretically, could the same be said of a brothel? Would we be allowed to do their laundry?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

Your distinction between the places that are designated for what is forbidden or which  mostly deal with what is forbidden on one hand, and the places that are predominantly lawful on the other hand, is a correct distinction.

This is because it is not permissible for one to cooperate with places that are assigned for immorality and dissoluteness, or which are predominantly so, even if one’s dealing with them is in what is permissible, such as supplying them with napkins, tablecloths, cooking clothes, towels, etc., as this is considered as helping the disobedient and dissolute people in their dissoluteness.

Those items are used in the preparation of such places or preparing the people who are running it, whereas it is an obligation to condemn their acts and not be pleased with what they do, and not to approve of what they do or help them in it.

The Shaafi'i School of jurisprudence stated that it is forbidden to prepare food for the women who (are hired to) wail over the dead because this is helping in disobedience.

Al-Ghurar Al-Bahiyyah reads: “It is forbidden to prepare (food) for wailing women because it is helping in an act of disobedience.” [End of quote]

It is known that the disobedience of hired wailing women is not in principle because of the food prepared for them, but it is forbidden because this food helps them in committing sin. The same thing is said about preparing places where Allah is disobeyed, or when help is given to the person who prepares those places, because such an aid is not permissible.

Allah knows best.