Duelbits gives rakeback, daily, weekly and monthly bonus to each user. All these bonuses depend on your wager and house edge of the game. Duelbits also give rank up bonus. Only $1k wager is required to reach the first VIP level. It isn't difficult to reach the first VIP rank. The bonus has no connection with deposits.
That much amount can be wagered by small gamblers also over few months period with small bets also.The duelbits have made this system after analysing the market conditions and also provide rakeback as you said which provides more benefits to players while wagering and reaching VIP first level and avail those extra bonuses.
When you think about it Duelbits is a little generous with the fairly easy achievement of reaching the first VIP with a total bet of $1k that's an amount all little gamblers can afford.
And what I love about Duelbits is the placement of the rakeback display which is easy enough to see on the first look making it easy for a customer to claim this rakeback.