It is not true. Because gambling is playing games and you can have a fun not risking your money. You need to pay for these games to play. But in investing you can make a good profit in the longer run if you make some decent decision and not all investments are scams.
A better practice must be doing a special thing for your special purpose. Gambling is proven, it is ONLY made for having entertainments. So we must avoid any attempt to use gambling as an investment.
I agree. I am quite disappoint when people say gambling is investing. Investing is making smart choices and doing risk management so that you are likely to profit. However, gambling is having no control over the results so you rely purely on luck.