LBS vs Online stores

Market rate is what a buyer and seller of a good or service agree. The issue here is that for skilled people with a bit of time on their hands there is no market rate because the price LBSs wish to charge is higher than the skilled amateur is willing (or able) to pay, hence the LBS does not get the job and, potentially, goes out of business.

But the skilled amateur is not the one using the bike shops. The LBS will continue as non-skilled (or more likely un-interested) cyclists will continue to use the LBS.

Again, you are comparing yourself as a keen cyclist who is willing to have a go at doing their own repairs with 99% of the population who are not.