According to meta-analyses on the topic assessing doses of 200mg vitamin C or more, vitamin C has failed to reduce the frequency of colds in the normal population but was successful in reducing the duration of colds (on average 8-14%);[149][145] when looking at studies investigating extreme physical stress (marathoners and skiiers), the risk of getting a cold was halved (which has been noted in past meta-analyses[144])
Definitely not a marathoner/skiier but I work out about an hour a day and I never expect Vitamin-C to prevent colds. I only take it after 2 to 3 day of sensing an incoming cold.
Pharmaceutical companies don't use marketing budgets to drive demand among the general population?
However, I disagree that they use normal marketing strategies with governments. They play politics instead. In this case they had the backing of the World Health Organization, and media outlets screaming words like pandemics every ten seconds. We all know that dead bodies don't look good on a politicians resume willing to run for reelection.
I agree that those materials were not glossy brochures and adverts with smiling mother and happy children, but those information packs are very definitely marketing and not just a dump of all the data they have.
That's partly why Cochrane had to struggle for so long to get the full data.