It's easy until you realize how global Facebook's audience is. What happens if California makes this type of advertising illegal for hotels and Sri Lanka makes it illegal for movie theaters? Now repeat for every possible advertising law.
The telecom industry is already 40 years down this path, the level of regulations, state, county and city E911 fees and operating regulations is impressive. If scrappy, insolvent players like Sprint can write code to comply with onerous, numerous and varying regulations across 7000 different LATAs, Facebook can handle writing code to comply with national laws in 200 odd countries.
Facebook (and others) can choose to show ads in any jurisdiction it wants, but if it does it has to follow the rules there. If they want to show ads in day Sri Lanka then they have to read up on and follow the laws there. In some cases it will not be worth it.
