We flew Delta. Maybe whoever you ask has a different answer. LOL.
The ground services at SXM are provided by 1 or 2 different local contractors. They likely set their own policy and it could easily vary by each contractor, each airline, each day and how the employee interprets the policy. I am not saying the inconsistency is right but you are not dealing with a Delta, AA, etc. employees in most cases. AA used to have 1-2 of their own people there to oversee things but not sure if they still do or not.