When you say free you don't mean free. Free means no one pays for it which means no one spends time making it. If anyone has to spend any time making and/or distributing this birth control it isn't be free by definition.
"When you see free you don't mean free. Free means [this thing I just decided it means, which is quite obviously not the meaning you're using]. If [the definition I just introduced doesn't obtain] it isn't free by definition."
Or they don't mean the specific definition of "free" you've concocted. Free can definitely mean "without payment" which one could easily infer from context and it's what GP meant.