Not every house functions quite the same way, of course. For example, the Canada House sits adjacent to the HHH, but the Mounties over there will stop you at the border; it's for athletes only. Likewise, the US House is an elitist operation for only Olympians. That leads to US athletes partying elsewhere -- sometimes, to their own detriment, in the case of one bleach-blonde American medalist.
As time passes, the hospitality houses are turning into something of an arms race, too. For example, Portugal set up its house inside a Portuguese naval ship, the Sagres, built in 1937, while the British House occupies what's essentially a castle at the foot of Christ the Redeemer. How very imperialistic of them.
The point is, however, that many countries have leveraged the Olympics into a place to promote their culture -- doing so inside the hospitality houses. Already, the Japanese hospitality house in Rio's called the Tokyo 2020 Japan House, so named to promote the next edition of the Summer Games in -- guess where! -- Tokyo. That one grants free admission, but clearly to spread the word about how great Tokyo is, and how great the 2020 games will be. And how great houses are.