A person who puts $400k on a gambling site has a larger deposit and is financially stronger. Everyone invests according to their financial status for their entertainment. Because the more financially strong his needs, the better his standard of living, so gambling is risky for everyone. For this, everyone should make gambling deposits and gambling in such an amount that the loss does not cause them any major damage.
Any millionaire doesn't put up a 400k balance in gambling because gambling can trigger someone to go all-in on one bet they have predicted chances of winning the jackpot, I don't think any millionaire would do anything crazy just to lose money easily because they will not be able to earn $400k/day even though they have a global company, I have seen some international artists never risk too high funds in UFC betting because they realize there are no accurate predictions in gambling.
The principle of millionaires is to use money for business rather than gambling unless they invest in gambling stocks, they also limit their financial use to gambling with the lowest allocation of funds.
I must say that I love your points, they are so precise. I said a similar thing in January or thereabout when I last posted here, the issue of being rich and poor is relative in gambling, and no one should generalize it to make it a measure gauge for all poor and rich people. What we should first establish are the amount the rich and the poor are willing to commit to gambling, the rate at which they want to commit it and the frequency of their gambling daily among others. Don't be surprised that the poor may love gambling more than the rich and gamble many times a day while the rich may gamble just once on that day despite having more money. The rich may just wager a little amount and will go his way, while the summation of all the daily gambling of the poor may be way more. Now, of course, if the poor are not addicted to gambling, they should not be doing that every day especially if it results in losses. Aside from addiction, something must have been causing the consistency, which may be regular winning or the fun derived from it. And if the reasons are from the two (fun and winning), then the gambler may still be doing fine since the money commented directly from the pocket to gambling may not be much on every risk-taking, so this is so relative to those factors.
As for the rich, they might also be gambling for fun or seriously as the case may be, and such would limit the amount risked. If your own case is to be observed, of course, rich people are not senseless too, they will moderate their spending while gambling. The fact that you are rich and worth $4m doesn't make you gamble $500,000 at a go, or else you will lose all your fortunes pretty soon. For this, everyone whether rich or poor must manage and moderate the way they gamble, nevertheless, their love for gambling, adduction, risk affinity and the entire benefits from it (money and psychological) will now determine how frequently it is being played by them.