The tourism "benefits" of hosting the Olympics

What does a few billion dollars of spending buy you? Per the Globe & Mail:

... in an economic phenomenon that repeats itself every four years, the Olympics have driven away most of the 300,000 tourists who would usually be in London over the summer ... 'The central London attractions such as the London Zoo, St. Paul’s Cathedral, Westminster Abbey and the British Museum are all seeing attendance figures down 30 to 35 per cent last week compared to the same week last year.' ... The hotel industry is suffering from the lowest booking levels in years. ... London’s legendary West End theatres have been devastated, their expensive plays abandoned by sparse crowds ... Restaurants have been hit particularly hard, having lost both tourist traffic and the custom of many Londoners, who have fled to the seaside or stayed home during the Games.

Of course it's also a more general thing:

It is a phenomenon experienced by virtually every city that holds an Olympic Games: the organizers and the government predict great tourism benefits which never materialize. In any city that already has substantial levels of tourism – that is, virtually any city that could qualify to host the Olympics – there is a lot more to be lost than gained from the Games. In 2000, Sydney hoped to see 132,000 tourists during the Games, but saw only 97,000, and experienced no growth in tourism during the years afterwards. Four years later, Athens had an even worse experience: Its organizers had hoped for 105,000 hotel guests per night, but received only 14,000. Greek tourism had not yet fully recovered.