What is Gaming Clubs Loyalty Cashback?

[Synergistic Explosions]

I was just playing Gaming Club and noticed my balance increased by $50. Since I wasn't close to clearing the $100 bonus I was going for I thought this was odd. So I checked the last ten admin events under playcheck and it said it was credited under "Loyalty Cashback".

Anyone know what this is all about? They are being so generous with 7X bonuses I find it strange they would just give this money out without explaining what it is.