Isn't it interesting that despite the ban on CFCs, and the lack of an exception for medicine, being something imposed by the government, your response is to blame the companies?
Don't get me wrong, I completely agree their lobbying is against the general interest of society, but it was the government that was elected to protect the interests of the public, and failed.
The point is, both the urge and the power to lobby against the interest of the people come from the private and profitable nature of their interests.
It was not a punctual failing of the moralities of the companies, it is a consequence of a system that stimulates them to do it and given them the power to do it successfully.
But what actually hurt the people wasn't the lobbying, it was the actual banning of the CFCs in medicinal applications, which wasn't made by company with private and profitable interests, but by the government!
What I believe you're missing is that the government is not an isolated entity in a vacuum. Its made of people and groups that make their case and express their interests.
In this case the interests of the private company prevailed. Notice that the proposal of not banning CFCs in medicinal applications was also a decision to be made by the government, but the pressure from the other side was simply not enough.
