I don't have time to read this entire thread right now, so I don't know if this was addressed downthread.
In regards to flu vax - I do not remember, in my childhood, pharmacies advertising for flu vax, or even any push for the general public to be vaccinated, only at risk populations, I don't know if that was due to shortages or lower productions, both at times I'm sure. My parents both had professions were they received flu vax and felt lucky about that. I think this screaming from the street corners encouraging everyone to get flu vax is fairly recent?
Pharmacists giving vaccines is a relatively new phenomenon. That's why pharmacies weren't advertising it even ten years ago; it has nothing to do with availability of the drug product. The number of states where pharmacists can vaccinate and the number of vaccines we're allowed to give have both been growing even in the past five years.