When I had it done, it wasn't available to 'single, footloose and fancy-free' guys at all (at least not on the NHS) - only married men whose families were judged to be 'complete'. You, and your wife, had to have counselling, and she had to sign that she agreed to the vasectomy or it didn't happen. 'Course things might have changed since the mid-eighties, but shagging around was absolutely the last reason I considered it. It was economic necessity that drove me to it.