Very few computer languages give their name to a file format. PHP is one. I'm sure you can think of others. But there are more that don't. For example, C and C++ do not, neither does Python, nor does Cobal. However, if you want to keep doing it, then obviously I can't stop you.
BTW - you say you thought it stood for Game Script. But what does the "c" stand for? Game Script Code? That doesn't even sound right.