Hmm, it's hard to explain. I didn't want to explain it earlier on because it would only make it more confusing.
There's a hidden feature in S3D that I have not yet fully implemented. Some controllers have so called 'optional' values, meaning that the value may be specified, or it is omitted. When adding blank new chunks using S3D's new feature, all optional values are also enabled and there is currently no way to 'omit' them.
In this case, the last value 'cmdr_AIMerchant' is one of those optional values. I don't remember where but it is used somewhere (in most cases it isn't), and I am not entirely sure what it does. If you don't want it, I can only recommend finding an existing controller that doesn't have this value and export/import it.
I hope to add a checkbox for optional values at some point so you can choose to omit or use them.
Hope this clarifies it a bit, I have been wondering for some time now when someone would notice
So kudos to you for the sharp eye!