Yes, it was there for me, after exchanging it goes away as the new BTG balance is zero. If you had a zero balance at the time of the snapshot then you would not be due any BTG so it would not be displayed.
surprisingly I'm entitled to 0.00068968 BTG which can be exchanged to 0.00001310 BTC
it must've recorded my balance before I lost it a month ago when trying to recoup my losses
If your balance is more than 2 times the total amount you received from free rolls then there is no captcha. I haven't had to do one for ages as when Google reCaptcha went nuts I made a deposit to turn it off.
I'm having very low balance below 30k sats in the last two months, and I don't see captcha at all now
It disappeared since my last deposit of 0.013 BTC a few months ago which I lost it a month later
managed to multiply slowly over a month up to 0.057 BTC then lost it
so, it has to do with total deposit amount, total free roll winnings, and maybe total wager