I my youth (far too many years ago now). it always used to confuse me when some American on a TV show or movie, would mentioned the Holiday Season.
To me, Holiday Season was the six weeks we had off school in summer. i.e. When we went on holiday. These days holiday season means July/Aug/Sep, i.e. when most people go on Holiday.
Took me a while to realise they actually meant Christmas, a time when traditionally you do have time off work, but most people don't actually go on holiday!