They do exist but unfortunately there is a lot of trial and error to find a good one. The LBS where I bought my first good bike was utterly useless. Neither I nor my sister could ever seem to get anything fixed right. Her shifting system never worked right despite being her bike having friction downtube shifters and I could never keep my wheels trued properly.

When I got back into cycling in the 90s I was fortunate to have a very good friend who opened a shop who still is (despite his shop being closed several years now) one of the best bike mechanics I have ever seen. He and I worked on my bikes together. Since he has closed and is really busy with his new job I have found another shop near my workplace run by a couple who have a good collection of sales and service staff who "get" customer service and I have never had an issue with their work. Minor repairs are often done while I wait and even fairly major ones are done on the same day. I have purchased two new bikes from them since 2006.