To be fair, that's because the label siphons the rest. Spotify pays $4 per 1000 streams.
ansc's number was $4 per thousand plays.
Your number is $3 per thousand plays.
It sounds like you basically agree with ansc. While Spotify might be cheap, that cheapness is not the problem Snoop is having.
You say: $450 / 150,000 = $0.003 per streamed track.
The two sets of numbers don't seem so far apart that the discrepancy cannot be explained by rounding errors.