Thats not in Paris (only first three minutes you see real Paris), its in Prague in Czech rep. and its tower called Petrinska rozhledna (smaller version of Eiffel tower-60 meters hight)near Prague Castle
Hell, everyone does that at the tower! It's really irritating seeing them keeping "a-look-out". If you get caught, you get caught! At least enjoy it without being paranoid.
check it: http://www.dragosroua.com/wp-content/uploads/2009/07/prague-eiffel-tour.jpg
I love Paris ;)