Cause they're doing some event and everyday sharing 5$ code with 800 user (but not always 100% claim in under 10-30 second). If you can claim all, you can get 15-20$/days + Weekly with 10K waggering every weeks + monthly with 40K waggering.
From the code potential 450-600$
I just tried to calculate the bonus drop amount of Stake from their telegram group. They have given almost $240 through the bonus code in their telegram group in this month (in 21 days). The annoying part is that most of the bonus codes are worth $1, $2 or $3 at Stake. A user need to have around $15k to $20k wager in the last 7 days to be eligible for all the bonus drops. If we include the weekly stream bonus code amount, then Stake also gives around $500 through the bonus code each month. But the reality is that it will be difficult to claim $100 from all these bonus codes. Because those codes reach the max claim limit within a blink.