I don't think we should discuss numbers which are so obviously non-sensical.
The EU had around 500 m inhabitants in 2016. You can't seriously believe there were only 137 m hotel nights consumed? (In fact, there were over 2.5 b nights consumed in short-stay accommodation establishments in 2016.)
Just quoted Forbes. Nothing more. (perhaps the 137M was non-EU folk stays?)
Not sure where your 'fact' comes from.