Scared Silly
Contributor
Pure "supply and demand" economics, nothing mysterious.
If there are lots of people who speak Spanish looking to get certified where you are it's very useful. However if you are in a Spanish speaking country and every other instructor is perfectly fluent, being of "intermediate level" fluency probably won't cut it.
But in places like Honduras being able to speak to the locals as well as tourists, many of whom speak English will put you on the plus side of a native Spanish speaker who has english as a second language.
But really the bottomline is learning a second language fluently is worth while.