Pre-covid, I used a bicycle as my main commute method for ~8 years in three different major cities. In my opinion, local bike shops are among the most corrupt and unethical business, and I eagerly await their demise.

I do most of my own maintenance, but for basic things and low cost parts (chains, tires, wheels) my experience is that bike shops lie about the necessity of replacements and bill 2-3x markup for parts, in addition to billing for labor.