Complex sentence: In Vienna, many restaurants are made to look like Heurigen but in fact are licenced restaurants selling wines from outside sources; these even serve beer and coffee, unthinkable at an authentic Heuriger.
Split into simpler sentences: In Vienna, many restaurants are made to look like Heurigen but in fact have a restaurant licence. These sell wines from outside sources, and even beer and coffee, unthinkable at an authentic Heuriger.