I'm not Irish, but I have an additional tendency to ignore St. Patrick's Day. First, I generally dislike any holiday that becomes a adopted day to drink, and drink to excess. I'm talkin' to you too Cinco De Mayo and New Year's Eve.
This isn't to criticize the ethnic bases of these holidays, just what they have become.
But St. Patrick's Day also has the additional detriment of being "gay exclusion day", so good for the Mayor of Boston (and Sam Adams Brewery).