Bike shops have always had a problem keeping high quality employees, and I usually seek out the owner, if the shop is a sole proprietorship. We had a couple of bike shops in our town growing up, and most of them had high school employees who were in to the BMX or freestyle scene.
Back in 1991 I was offered a job in a bike shop on my 16th birthday (earliest legal age to work) because the owner was a family friend, and he was sick of his BMX'er employees stealing from him and showing up late. I knew nothing about bikes, but I pored over the product catalogs, absorbing all of the subtle differences between bike models and groupsets, and quickly established myself as the shop "techie". I also picked up the mechanical side of things quickly.
It was the the beginning of the hard tail mountain bike boom, and then soon after came the beginning of the hybrid boom--certainly not the most exciting era for "enthusiast-level" bike sales. But I studied the catalogs at home at night and learned the price points. Even though I wasn't a "salesy" super outgoing person, I quickly became good at selling bikes when certain customers realized I knew what I was talking about. Having knowledge of the ins and outs of different models gives a salesperson credibility, and to this day I always seek out the most knowledgeable salesperson I can find in any industry over the guy who just wants to buy you a steak and a drink.