Agreed, something really fishy.
Anyway the amouny of people that can actually use the site is pretty low as the site is being limited for XRP bets, not a large amount of people holds XRP, and those who hold it usually do that for investment cases so I can't see them gambling on their investment.
You will still need to give as an explained reason why you were trying to sell the site few weeks back
Also this is not listed under licensed version here
https://www.bustabit.com/license.txt so script can have backdoor.
May be he thought it will be great success as people are going crazy about XRP these days but in fact he never got any big player.
10
BTC for this site is just overestimation.