It works as a thought experiment. If someone at a restaurant refused to handle pork products, but was seen on Facebook eating a BLT. Is it the employers place to interpret their religion?

Similarly many Jews disagree on the definition of work on the Sabbath. If a Jewish person took off on the Sabbath for religious reasons, is the the employers place to tell them they can't turn any lights on, or use the oven?

(16:115) He has only forbidden you dead meat, and blood, and the flesh of swine, and any (food) over which the name of other than Allah has been invoked. But if one is forced by necessity, without wilful disobedience, nor transgressing due limits,- then Allah is Oft-Forgiving, Most Merciful.

So only meat is banned and only when it's not "necessary" (which is really open to interpretation)