To hang out or say hi? sure, ER docs are more than welcome. If anyone wants to give an update on a patient, why not?
To raid the EMS snacks or fridge of cold drinks, which I have seen many of the ER staff do, especially during EMS week? now that's a different story.
Random aside: the CEO or CFO (I don't remember what he was) of my hospital based EMS service used to stop by EMS quarters occasionally... Apparently he liked one of the drinks we had in our soda machine, and it was the only place on hospital property that had it (something like yoohoo or Dr pepper). Nice guy, never busted our chops even if the lights were off and we were in siesta mode.