So, I got some free time at hand today and curiosity gets the best of me. So, in a wish to close this case for good, I threw myself into the site in question itself to see what's this boosted bet by their definition.

It's funny how you said earlier that you never use any bonus and never cheated, that you close your accounts simply for personal reason, and that only after I pointed out that you had your bet on boosted mode, you added a claim that it's not a bonus or promotion, because clearly their guide page said the opposite:


 

The boosted bet is clearly listed on their promotional page, and given you utilized this not-a-promotion thing, I am quite sure you also aware about this. But that's not the end of it, as I said, I have some free time at hand, and since I wanted to get to the bottom of this and think there's more to these... accounts closing and reopening, I took one step further and dig deeper: I made an account on SB, just for you and this case.

Guess what I found? This:



Apparently --at least to me-- although you can use a boost for one sport every 24 hours, the amount of this promotion is not unlimited. In my case, I have 39 free boosts. So what do I need when I ran out of boost? Well, I guess I can just... feel I've got enough, close my account, and then open a new one few days later. Voila, new boosts.