https://mashable.com/2016/05/12/china-bottled-air-demand/
Curious I googled the company to see if they still existed. Vitality Air appears to be doing well.
> Modeled after the "air stations" in polluted downtown Tokyo and Beijing, the first oxygen bar (the O2 Spa Bar) opened in Toronto, Canada, in 1996. The trend continued in North America and by the late 1990s, bars were in use in New York, California, Florida, Las Vegas and the Rocky Mountain region.