The reason they do this is to get you playing at their site. They make more off of your rake than they are paying you for a bonus. Well, that's not entirely true, but if you stick around afterwards, they certainly do... plus it gets more people on their site and so on and so forth. It's good business.
BTW, Badblood forgot to post a link to Empire, so I will (no need to use that bonus code with this link either - it's built in
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