This is an area where English is simply deficient and Chinese excels. Where a single pronunciation and spelling in English is ambiguous, Chinese characters differ and make the exact meaning clear. We really need to be verbose at times in English in order to not send the wrong message.
-Renegade

You then go on to give some examples that clarify the meaning rather than using the word "free".
As a constantly evolving and highly flexible language(s), English gives a vast range of options to its speakers. Ranging from words that define meaning precisely, to usages rich in allusion or insinuation, to usages (frequently colloquial) that almost seems designed to allow the maximum range of meanings to be eked from limited vocabularies. Precise meaning can come from the individual word or word groups or can arise from the context.
The whole "free" thing arises from people enjoying the word play the word 'free' offers.
Admittedly, it also seems to have been deliberately misused in this thread to imply things that were never meant. "Free market" and "free speech" are usages where the meaning is defined in the specific word pair rather than the word 'free' as an adjective. Just as there is a misuse of the concept of 0 in an equation. Simply people having fun, I assumed.