Gambling as an investment is not mostly admitted by gamblers, because they would have been on it for some time now and found out to be of no difference to what they see if they had not invested, gambling platforms also suffer regulation challenge and they may not be able to allow all these to be offered any longer to gamblers because of government regulations, which are not applicable to allow us have access to even if the casinos want to offer them.
Gambling definitely cannot be considered an investment, because in the long run, casinos and bookmakers will beat the player and take their money that's how this business works. Gambling can be considered a profitable business if you are the owner of such a business and provide gaming services, then yes, you can make good money on it, even though the competition is very high and there are quite a lot of gambling sites today.