Look, I'm afraid that you've missed the point of the "humour" in such utterings Sandy. You can see where that "turn the other cheek" attitude has got us , and I am not just referring to "Irish Jokes", I include this type of put-down against English, Scottish, Welsh., you name them, as well.
Yes,I am offended (but far from mortally wounded), as an Irish person, that we should be stereotyped as "dirty" "ragged" lice-ridden etc, , whether in song or prose or in the media, by derogatory clap trap "humour".
However if some prefer to play the part of "court jester" for ever I hope that their skin remains as thin as that of the balloons on their giggling sticks if that is what it takes to accept insult without offence, god knows there are many like that.