You are correct. A warrant gives the holder the option to BUY at the exercise price and the warrants are not "paid for already", technically.
Here's the kicker...
There are two ways to do a cashless conversion.
1. You do the conversion and the exercise prices is deducted from the proceeds of the sale.
2. You do the conversion based on a formula, and no proceeds go to the company. You just get fewer shares if the formula dictates that you are "in the money"
Unfortunately GBSN's "formula" has a "technical inefficiency" granting the C holders astronomical amounts of free shares at these low prices.
It is a major negligent oversight if not criminal and I'm having a hard time believing they didn't see it coming.