The point of the article is that this is an expensive mess for everyone except the manufacturer, which means approximately everyone. As a consumer, having the manufacturer "transfer" money from your pocket into their own sucks. Seems like the article's logic is actually pretty decent.
Also, even if we accept that the marginal cost of producing a pill is near-zero, that's ignoring the entire rest of the supply chain. It's not like drugs are magically teleported. There are real costs in time, money, and resources for creating the packaging, transporting drugs, stocking/shelving them, unstocking them, sending them to a disposal location, and then disposing of them. All of that is a complete loss. Most of it generates various forms of pollution, waste, and other externalities. This also sucks for ~everyone.
Basically, outside of theoretical econ-land, wasting perfectly good things is wasteful.