The answer is priceless:
Opening a café in is forbidden due to what accompanies it and to what it entails. A café is a place where people buy coffee and sit to drink it. In the West, cafés are places of mixed genders where men and women [those whores!] sit at the same table. Often, lovers would sit together and God knows what they would be wearing and what they would be doing in that romantic place.
My guess: Drinking coffee and chatting.
If the café is for one gender, e.g. men, then the problem is worse. Do you think that you can open such a place, and make halal business and gain halal income from hosting lovers and offering the half naked people a shelter?
Oh no! Not the half naked people! Allah have mercy!
I hope that you do not say that I want to make a halal café; as this in our time looks like carpeting the ocean. Do not think that opening a café for Muslims will make it halal, as a café is a usual place for gossip, where, men would sit by the sidewalk watching women by-passers, where men would sit to play card, or backgammon both of which are forbidden and often the café owner provides the cards and the tables.
I didn't know that Allah / Muhammed hated Canasta.
This is the type of low-level idiocy that the Islamic world deals with every day: A freakin' café opens the path to hell.