Considering cancer, heart disease, or dementia aren't contagious, my individual treatment decision does not threaten those surrounding me.
I want to know as much as possible about treatments, their side effects, and tradeoffs. And if I partially learn about those items from a commercial, who cares? I want more time with my friends and family. I don't care about the source of a potential solution.
And the doctor can still elect to not provide the medication. The treatment decision is expertly gated, regardless of my wishes or insistence that "I know better".