Such bonuses usually have a wager rule and an expiration date.
https://boards.streamweaver.app/showthread.php?tid=28743
http://biopharmamash.com/viewtopic.php?t=1829943
http://myweed.rocks/viewtopic.php?t=67378
https://67farms.st/viewtopic.php?t=9329
https://www.ww2.site/forum/viewtopic.php?t=382322
https://muchroom.ng/index.php?topic=35424.new#new
http://oldsite.giessen46ers.de/fantalk/viewtopic.php?f=1&t=190521
http://www.lada-xray.net/showthread.php?p=294971#post294971
https://my-mobile.eu/viewtopic.php?t=16063
https://67farms.st/viewtopic.php?t=23407
http://oldsite.giessen46ers.de/fantalk/viewtopic.php?f=5&t=244004
http://wirtualnapolityka.cba.pl/showthread.php?tid=10517
http://60.250.226.63/ipkb/viewtopic.php?f=41&t=1951861
http://mirosovak.edoras.cz/viewtopic.php?f=3&t=483642
http://www.horsecity.ru/phpBB3/viewtopic.php?f=33&t=163141
http://labradory.info.pl/viewtopic.php?f=3&t=25175
http://wirtualnapolityka.cba.pl/showthread.php?tid=9517
http://wirtualnapolityka.cba.pl/showthread.php?tid=9448