Actually, this is fueled by the tendency of the non-Irish to confuse Irishmen and Scotsmen. The Scottish evolved small penises because of their tendency to run around freeballing in a battlefield with nothing to protect their willy but a wee kilt!
Dumbass: Hey, why are you wearing that golf cap?
Irish guy: It's a fooken Irish cap
Dumbass: What, so you're Irish?
Irish guy: No shite!
Dumbass: You're suffering from the Irish curse. Am I right?
Irish guy: It's the Scottish curse, ye dumb fook!
Dumbass:There's a difference?
Irish guy: *sigh* I'd beat ye to death with me own dong but ye'd probably like it. *shoots the dumbass instead*