I think if people do not understand the difference in at least some cases it may be
some might not ‘want’ to understand the difference.
I do not se any major problems with people understanding the difference
between eating a full meal at a Pesach Seder or Sukkoth and eating less (or sometimes not at all) during each weekly meal.
I do not see any major problems between understanding the difference between eating kosher or not kosher, or between Torah study and secular studies.
Could it be that those who do not understand the difference between drinking on a bit more on Purim (and lets remember even on Purim we are not supposed to drink to the point of sickness and vomiting) and less during other times, are simply looking for excuses?