I never had one. I did get advice 41 years ago that was literally lifechanging: to buy at shop discount the last year's Fuji Professional sitting in the basement of the shop I worked at as a second year bike racer. Fuji Pros were very steep, very high BB criterium bikes. My forte was long races and big climbs. The more of each (hours and feet climbed) the better. That Pro had 64 seat tube and 75 head tube angles and a decently long top tube, putting the headset far forward. Very short chainstays. 175 cranks. From the first ride, it was "wow!". I rode it very easy my first time around my 45 mile training loop (the still famous "Allis Loop" west of Boston). Matched my best time ever. 3 days later easily took a couple of minutes off that nad the times kept falling all the rest of the summer. I went on to race some very hard races on it, put in days of 175 miles. That bike just felt like part of me; that it could extract every resource my body had.
I have used that bike's geometry for the basis of every bike since then. Yes, there has been some real changes over the years. But not in my basic position: cranks, seat height and setback, and where my shoulders should be. I've had a few bikes that didn't measure up but every time I returned to that basic position, it was "oh yeah!".
So I have never felt any need for a fit. But if a $250 fit got me what that shop mechanic's free advice did. it would have been the best bargain of my cycling life.
Ben