Being out of stock at Woolworths proves that there is demand at...

Being out of stock at Woolworths proves that there is demand at the store and that the product is selling.
Don't worry about it going out of stock, WOW's business model is to try to turn their inventory over as quickly as possible rather than have any product sitting there for long periods. Turning it over quickly reduces their working capital requirements.

Proven retail demand is good as it demonstrates the product is successful. What gets really exciting are commercial/industrial applications.