Praise be to Allaah.
Firstly: it is haraam to work and earn a living by helping people to consume haraam things such as alcohol and pork. The payment for that is haraam, because this is a kind of cooperating in sin and transgression, and Allaah prohibited that when He said (interpretation of the meaning):
“…but do not help one another in sin and transgression…” [al-Maa’idah 5:2]
We advise you to keep away from working in this and similar restaurants, because this will keep you from helping in anything that Allaah has forbidden.
Secondly: it is forbidden for a Muslim to sell haraam things such as pork and alcohol. It was reported that the Prophet (peace and blessings of Allaah be upon him) said:
“When Allaah forbids a thing, He also forbids its price.”
Provision and the attraction of customers are things that are in the hand of Allaah, and they are not to be found in selling haraam things. The Muslim must fear Allaah and follow His commands and heed His prohibitions.
“And whosoever fears Allaah and keeps his duty to Him, He will make a way for him to get out (from every difficulty). And He will provide him from (sources) he never could imagine” [al-Talaaq 65:2-3 – interpretation of the meaning]
Sheikh Muhammed Salih Al-Munajjid