Can you provude the ToS for that promotion. How the heck you manage to wager the bonus while you don't have any deposit on that casino? On what kind of promotion you get that bonus money? It seems a very weird promotion to let user play using the bonus while they will not let the user withdraw unless he will deposit same amount of money. I think that's very suspicious same with the casino indicated on the screenshot.
You should not be able to play unless you will the minimum requirements to get that particular bonus. Just a hunch but the casino is very shady. Keep away.
Do not judge if we do not know the full terms and conditions related to the bonus. Every casino has their own terms about bonuses especially no deposit bonus. In this case we should know about the no deposit bonus which is taken by MNbag before judging the casino too far away without clear information.
What if he deposit a money on this site and turn into a scam? That bonus might be a click bait to attract more gambler but in reality they wont pay at all. I don't know, I just don't think an easy money like this will happen on a gambling site, not unless they really have this kind of promotion and it clearly says on their ToS. Don't be greedy, if you can't afford to deposit some money then that's ok, you can still have more bonusses on other site, there's a lot of options for this especially with a legit site that have a deposit bonus.