Short answers:

"Because no one's told me I can't and made it stick."

"Because it's so very, very comfortable."

"Chicks dig it."

"They may take our lives, but they'll nay make us wear trews."

"It's an easier midlife crisis than chasing after young blondes and old whiskey."

"With legs like these, wouldn't you?"

"I'm Scots, Scots-Irish and a touch Welsh by heritage, and I'm as proud of where I come from as where I am."

and only very very rarely

"The voices in my head tell me to."