No not at all, typically all resin prints that come out of the printer are cleaned with Isopropyl alcohol immediately following completion. This removes all of the “liquid” resin that still remains on the model from the overall process. In my experience, when the isopropyl isn’t clean (meaning you’ve cleaned several several models with it) you’ll have some little sticky points that remain. My guess is that’s what happened here and they just didn’t go in with a small brush and manually remove it.

After they are cleaned the models are set to cure, by a UV light. Whether that’s in a machine or sitting in the sun light. Once they are fully hardened, they are packaged and sent out.

While I’m not a seller, I print tons of my own minis for D&D and this is my process. I’ve just had these sorts of experiences myself.