I did receive a reply to the email I sent asking the company (Henkel) if Sta Flo was being discontinued, below is their response:
Thank you for taking the time to contact us for information about the availability of St-Flo Starch.
We understand the difficulties in locating the product. The product is in minimal distribution that it may be hard to really be found. It is possible the store may be temporarily out-of-stock, or management may not realize the demand for the item. If you can't find the product, on the shelf at your preferred store, please speak with the Store Manager. Surely our Manufacturing Team will also be notified and be made aware of the demand of the product.Thank you for contacting us and have a wonderful day!Sincerely,
Team CleanHenkel Consumer Affairs
Unfortunately, they did not directly answer the question about discontinuing production. I do know that at the 2 Wal Marts I have checked, there in no longer a place on the shelf for it.