It's probably a liability concern on their part, but they also want people to have money to trade in the future too. If Robinhood users had any chance of actual

It's probably a liability concern on their part, but they also want people to have money to trade in the future too. If Robinhood users had any chance of actually making a bunch of money on this it would only be in Robhinhoods interest to allow people to continue buying. (if their users have more money in the future they will trade more)