If you use a funnel to put it into a gallon milk jug, and put the cap back on, why would it be a problem. My husband and I were paid to take part in an experiment and had to provide our daily urine output. The gallon jug system worked just fine. We dropped it at the lab, and they gave us a clean jug for the next day.
Have you calculated how many jugs of urine would be required to replace the 200 million metric tons of fertilizer used worldwide each year?