I think it is fear and fear, fear of losing, fear of missing out, fear of giving back profits, fear of pulling the trigger. There is no greed in this to me any more. We all have some type of fears or frustrations.
As a scalper, most of my trades are getting in with limits and I am waiting for price to get at some area I believe the market will stop, I think most of those on other side of the trade are those just getting in that have no rules but trade by the hip, many beginning traders who lack patience just jump in. They all have to learn one day, maybe.