i think you might be missing the reason SmartRewards exist, for overall stability, not as a means to reward smartnode holders, it is an additional benefit on top of the incentive that is SmartNode payments, they are separate features with separate goals. if you look back to the charts between july and october 2017 you can see that significant dumps were happening due to their being a grace period between payout and snapshot, this lessened alot once the grace period was removed, essentially smartrewards are a loyalty based reward, not a dividend and should not be though of like they should pay like one either. if your loyal to the SmartRewards then you get them.