A: To get to the other side.
Wait…no. Seriously, this is a question pondered by sundry and wiser men than I, yet still unanswered with any certainty. From Aristotle to Darwin, thinkers and scientists have proffered such theories as left-over vestiges from a “father feeds the babies” evolutionary history. This may be possible – after all, we have the whole (albeit underdeveloped) setup: nipple, mammary gland, nerve endings, blood vessels. It’s also still possible to cause male lactation with either enough estrogen or enough physical stimulation (in rare cases). But we generally don’t see men lining up for estrogen treatments so they can feed their young’ns.
I tend to stick with the whole “pleasure potential” explanation myself.
That’s it! Ask Dan #3 fades into the vague memories of the 6 (or dare I be so haughty as to assume 7?) occasional readers of my verbal drivel. Keep a sharp eye for the next Ask Dan installment!