You don't ask, you just head for the toilet.
Anyways its pretty clear that the guy is not right, he is clearly dazed in the video that so kindly provides a close up of his face. To watch another person in distress and do nothing is one thing, to sit by and take extensive, detailed video and post it online is heinous.
Nobody does this kind of thing willingly in public.
Kudos to the security guard who had the kindness to hose him off.