They are a form of deposit match bonus offered by casinos to returning customers for making additional deposits after the first.
https://www.chargersixpackforum.com/for ... A1m.72619/ https://ufr-2020.front5.picapo.net/foru ... pid=510167 https://forum.arduionly.com.au/showthre ... tid=171995 http://www.horsecity.ru/phpBB3/viewtopi ... 3&t=283290 http://horsecity.ru/phpBB3/viewtopic.php?f=14&t=223902 http://www.gztongcheng.top/forum.php?mo ... 826&extra= https://neoternia.net/viewtopic.php?t=153622 https://debate.socialism.nl/forum/showt ... tid=142202 http://forum.fretky.cz/jak-ji-naucit-na ... 74446.html https://www.rcfl.com.hk/forum.php?mod=v ... 544&extra= https://pornshare.org/Thread-Jak%C3%BD- ... tky-Online https://neoternia.net/viewtopic.php?t=241794 http://forum.bandingklub.cz/viewtopic.p ... &t=1284354