The Walmart stuff is ammonia based - not polyquat. I did see polyquat at Kmart one time - surprise and shocked, pleased too - I bought up all three quart bottles. Now they stock the same as Walmart. I only use polyquat at closing to prevent algae while the winter cover is on. For swimming season algae, nothing beats chlorine - Bleach
We had an Intex for many years and only used it right at start up in case there was some lingering algae from closing and storing. I used only BBB for regular maintenance - perhaps they suggest it if there is an underpowered pump and filter connected to the pool?
The Poly 60 suggestion assumes the reader is new to pool ownership and provides some algae "insurance" in case you do not have a good test kit or get lazy maintaining you water. If you keep your water balanced daily, it's not needed.