Yes the local shops will be open as will some bars, but it will not be very busy as the weather is not so good during those months, of course you will have nice days but generally not so warm. Imagine Great Yarmouth or Skeggy in the winter and thats it. I'm off on the 17th Dec and will find plenty to do Barcelona is just an hour away and you can't get better than that. Don't bother packing your shorts.