Whales are largely a myth told by video game (and gambling) companies to hide the truth of who they're actually targeting and to keep you blaming the wrong people.

They want you to blame the dude with more money than the church and not enough brains to know the difference between cents and sense, but the truth is that the vast VAST majority of money made through lootboxes and other forms of gambling comes from 3 sources:

Kids aged 15 and under, people with addiction issues, and people with mental health issues like depression or neurodivergent conditions like ADHD.

Game companies hire psychologists to develop the most effective ways to exploit the way the human brain functions in order to maximize the amount of money that they can squeeze out of people, and all 3 of these groups suffer from the same issues that they exploit: poor impulse control and difficulty with keeping track of how much they're actually spending. Kids because their brains aren't physically developed enough yet, addicts (and people with ADHD to a lesser extent) because their brains are literally wired that way, and people with mental health issues have reduced capacity for both and are more likely to seek out things that promise quick access to dopamine and serotonin (think "retail therapy" or self medicating). Also of note is that researchers suspect that kids who grow up spending money on lootboxes and micro transactions in general are more likely to develop addictive personality issues later in life - basically being groomed into gambling addicts.

That's also why they never let you buy stuff directly with money and use fake currencies that don't have a 1 to 1 translation - it makes it 10 times harder to track how much you actually spent. It's also why you can never buy the exact amount you need for an item: if you have currency left over, you're more likely to buy more so that it isn't "wasted".