As the designer, as long as you include a license file forbidding commercial use, then of course you are right, they would have to follow the rules you set out. Most licenses begin by saying something like "by using this font you agree to these conditions..."

However, if someone prints your font out and traces it, then most courts would not take your side if you argued that tracing violates your copyright. Even if you wrote "no tracing or derivative works!" in the license, you couldn’t enforce that; because copyright doesn’t protect typefaces. It only protect fonts when they are trademarks registered as "software".

The only exception I know of is if you have a "design patent" which are extremely rare, only a few have ever been issued in history. You have to convince the courts that your logotype is not (only) a typeface but a patented image of your brand identity (like the Coca-Cola logo, for example) then you'd have to pay about 700 USD extra plus court fees) And the courts almost always deny all typography cases...as soon as they heard "Well, it IS a free font, however—" they would laugh you out the door before you could finish: "...but the license says 'no commercial use!'

I am not saying the system is fair. I'm on your side. But you should at least find SOME comfort in the fact that in the digital age typographers can copyright their fonts at all. Back in the letter-setting days, the supreme court said type is nothing but a collection of letters, necessary for printed language and communication and trademarks would hinder the freedom if the press. So every foundry copied each other, and that’s why there are a million versions of Garamond and Didot and all the classics.

Maelle, what point are you trying to make, other than to illustrate a commercial use of a typeface? I see that you linked to a free font here at dafont, which I am not familiar with, but as I've said before elsewhere on this forum, free fonts don't always allow for commercial use: one would have to read the end-user license agreement or contact the typographer. Still, what does your post have to do with the question asked, or my answer? The OP has said that the design in question is a vector not a typeface.

isn't that something you would NOT want to advertise?

If this logo of yours was traced — even from a copyrighted, patented, and/or trademarked typeface and/or font design then you are fine from a legal standpoint. Any traced version, even one that is visually identical would have its own unique digital signature. Someone would need to analyse the original vector file itself to see if the outlines matched this copyrighted work exactly to definitively know that if the rights of their work had been infringed upon or not. A raster image uploaded to Facebook simply does not provide anywhere near enough info to make that determination. What you are describing sounds like the attempts of a desperate scam artist, not a legitimate type foundry. If you hear from them again, tell them them email you from their foundry's official email address with proof of their ownership and claims, and how they made this impossible determination. As it probably is a scammer, you probably don't want to give them your main email address.

Typically (though laws differ dramatically internationally) typeface designs cannot be copyrighted, but fonts are considered "Software" so they can be. You have to read the EULA (End-User License Agreement) for any font you want to use commercially—many free fonts are only free for personal use.

But I think the question is asking the opposite: not a logo based on a font, but a font based on a logo. This depends. The Coca-Cola logo is a good example of something you cant copy commercially, because the custom type (which was hand-lettered) IS the brand and the logotype at the same time. Yes there are rip-offs (I think there are some here on DaFont) of the Coke-style script, but one could get sued for copyright infringement and brand-dilution if used commercially. Many companies choose to use custom typefaces not otherwise for sale in order to set themselves apart. Marlboro cigarettes typeface is an example. At some point it was digitised as a font for internal use and marketing, but you won't find it for sale at any retailer.

In either scenario (creating a logo based on a font or a font based on a logo) regardless of the laws in your country, it is perfectly legal to make "derivative" works as long as they do not originate from altering the digital font of another foundry or designer, but you can print out the glyphs and trace them, scan them in and make a font. Every font has a unique digital fingerprint because it's code is a mathematical representation of its vector outlines. Even if two fonts look absolutely identical and indistinguishable to the human eye, any computer can tell the difference so you'll be safe from legal repercussions.

Of the numerous articles and resources I've found that define the many abbreviations in font names, this is perhaps the most complete:
http://help.fontshop.com/hc/en-us/articles/202693665-What-do-all-of-these-abbreviations-mean-

Also check out the Periodic Table of Font Elements @ Flickr:
https://www.flickr.com/photos/fontshop/4134128747/