Some people probably pm'd them and told them that people are using the SN for ctbing. Or maybe they just read a few news articles, who knows.
I wasn't planning to buy SN, but I feel sorry for those that were. More options is always better. Of course it's possible to ctb by taking sodium nitrate (the same stuff every one of us has in their kitchen), but I'm pretty sure it would have been easier to do it with SN since SN requires a much smaller dose.