The best thing is to look for the all types of gamblers on your casino and if we see there are large portion of small gambler on casino who are not able to wager more so such promotions for them is really helpful which is why duelbits is choice for them.
I agree that some promotion of Duelbits doesnt require wagering requirements at all when claiming especially on the sports betting reward like boosted odds and free spin but I just notice that Duelbits doesnt offer a bonus that has an insane reward which other casino like 300% above bonus deposit and so on that typically backed by a harsh wagering requirements.
So far Duelbits only offer a medium tier promotion except their Christmas giveaway thats why most of there promotion doesnt have have strict wagering requirements. Duelbits knew well their customer and how to approach them withpromotion that doesnt have a difficult requirements.