yes that is a fact that gambling can be consider as high risk investment. gambling is totally depending on luck. there is no concern of experience and skill therefore it is mostly consider as high risk investment.
Only a fool consider this as a high risk investment, this is nothing close to an investment . You lose money in here while investment suppose to get you more money in return. This is a very lame statement given that you should know very well that this depends on your luck and most of the time people are not lucky to win