Thats pretty common in every gambling sites. A top dice sites obviously have higher number of faucet claimed per minutes imo
Abandoned is not the correct words for it more seem to be like less time to manage the site therefore the owner left it there with the hope that everything will be going smoothly while he is not around.
If you check on the site you will see that there are about 300+ BTC investment just from oldmate alone which means that oldmate knows that the owner isnt going anywhere just less time to manage the site for now because no sane person will keep his 300+ BTC in an abandoned site if he got no information from the owner