You appear to be confusing fact with opinion.
You don't feel it will do any harm. Others disagree. Personally, I feel it would harm the trust between the developers and the community if they state something will be a one-time only offer then offer it again. There are those that may have subbed that month specifically to get the item. I actually know a couple that did.
If they can't trust that this will be one-time only, how about legacy benefits, could we then trust that they won't be given away again?
Or the CE items that people paid for a digital upgrade to, could we trust that they won't be made available in the near future for free too?
Offering perks that were specifically stated as a one-off, limited time deal a second time is a damaging precedent to set.
Opinions are not facts.