Sad but true it's a real life business model that works.
People really click on those links and buy the advertised mediations. Sometimes only a few per thousand but if you send a million of emails...
Most of these life style drugs are not real medications like the stuff sick people need. Also most of them are cheap generics or even counterfeit or fake drugs. These might be even dangerous.
That's the reason the only channel you can sell them is outside the proven medical sector.