Oh no! That's not a stupid question at all! Maybe we just took the audience for granted.

In short, the more used a coin is, the more value it has. Just like Bitcoin drops when it's banned, and gets much more valuable as more people us it. When only a few were using it was 30 cents and the more it gets used the more it's more valuable.

With the SMTs all these media coins will be on the STEEM blockchain, so the wider the combined use of all, the more valuable the whole thing will be.

Hope that helps!