Often SA's remove protective plastics before putting an item on display. Or they fall off. In some cases, it is difficult to do a proper inspection of the item if the plastics are still on. If the bag was in pristine condition other than that I would consider it acceptably new.
It is usually impossible to tell just by looking if an item is new or if it has been used a little bit - that is up to the integrity of the seller.
Well I'm familiar with Hermes but I am with LV. If I bought a LV item from Ebay and it looked brand new but didn't have the protective plastics on the zipper pulls I'd still be perfectly happy. As Northerndancer said, LV SA's will remove them oftentimes. I don't know if this is common practice with Hermes.
There was a thread about this on the Hermes forum a few months back.
In some stores, the policy is to remove the plastic from the bags - seems to be more in Europe than the US. When I bought my B, it had all the plastic in tact. However, another bag had no plastic. Same is true with the piece of felt that they use on the flap. My SA didn't give it to me - I saw it when I was presented with the bag but it was thrown out prior to the bag being re-boxed. All stores and SA's are different and have different policies. The removal of plastic does not necessarily means the bag is used because the store could have done the removal as per their particular policy.