octave:1> price_per_datapoint = 150 / 500000
    price_per_datapoint =  3.0000e-04
    octave:2> datapoints_per_months = 7e9
    datapoints_per_months =  7.0000e+09
    octave:3> revenue_per_month = datapoints_per_months * price_per_datapoint 
    revenue_per_month =  2100000

I guess they have discounted volume plans, otherwise it's looking too good to be true ;)

UPDATE: using their 20M datapoints for $1600 plan, 7B datapoints per month would bring "only" $560K revenue per month.