I can see how Medadvisor would work in Australia or NZ because...

I can see how Medadvisor would work in Australia or NZ because the pharmacies just don't have scale (in total in AUstralia ~5000-6000 pharmacies), but in the US wikipedia is saying ~88,000 pharmacies and chains like Walgreens or CVS have over 8000 locations and even walmart and rite aid have 3000-5000 locations each so surely if they get to that scale, they could develop something in house.

Perhaps they are offering their software for free to those US chains in order to gain access to their clients/patients because the business model there is for the drug companies to pay to access a broad client base (through digital marketing mainly) and less dependent on the pharmacies paying for an app as is the case in Australia.