Can sitting down gives hemorrhoid?

I have watched some Hong Kong TVB videos and they said one can get hemorrhoid by sitting in a taxi for too long. According to the movies, the taxi drivers get it because they sat for too long and cause the blood vessel to get jammed.

I check for treatment for hemorrhoid and do not seem to find any evidence to this. It is due to bad eating habits that cause constipiation that is the culprit.

So, do you think it is true?