If they have a daily 10,000 gallon capacity, I would assume that they generally produce and ship less than this on most days. Simply, running manufacture capacity at 100% means your missing out on sales and not keeping up with demand. You have to have reserve capacity for big orders etc. So, I would assume some fraction of 10,000 gallons is sold on most days.
Possibly.
Do you think this is a realistic scenario?
Instead of manufacturing an average of 10,000 gallons daily (= "capacity"), they run an average of 2,500 gallons daily? 2,500 gallons/day x $8/Gallon
Equals $20,000/day
Per year (exclude weekends/holidays & equipment maintenance): say 200 days/year
200 x $20,000/day = $4 Million/Year
(which is the same amount as what Gary mentioned in recent podcast as a minimum expected level of annual sales).