Many questions seeking tools are of the form, "Where can I get a free tool to do Y?" or "Where can I get an 'open source' version of X?" [which usually just a disingenuous version of the first question, OP has no interest in the source itself]. See the list of questions proposed as exemplars for Software Recommendations.
I'm all in favor of free and, er, open-source, tools and some of them are even my best friends (EMACS rules!). But often the answer to such a question is "There's a very low cost version called Z" or "You can't, only commercial versions exist".
When a question explicitly involving the request "free" is involved, are only answers for literally free tools allowed? If the question is "open source", are only answers for really open source (which doesn't necessary mean free) allowed? (Winzip is arguably free for a time. It isn't open source. There are packages which are not free, but are open source).
If there are paid versions, should it be the case they they are only mentioned in response to a separate question? Only if the adjective "not free" is included in the question? Should "free" and ahem, "open source" programs be include in questions for commercial tools?
My personal belief is that the words "free", "paid", "commercial", etc. should be left out of the question, and added as an attribute of a recommended item. Then the utility of the question goes up, because all the usable answers are collected in one place, and no information is lost.
Proposal: Software Recommendations