Add 1.32 to whatever numerical value you've attached to "killing", divide it by 2, and you'll have the average salary of some guy who runs an LBS. Are we really having this conversation? The LBS owners I know make better than minimum wage, so I'll decline any invitations to the make-believe world where they spend half an hour to make a buck and a half on a $30 transaction. Get real.

A typical spoke costs a shop less than a dollar, including brass nerp. The typical wrench makes, on average, $12.15 an hour. So, there's $25 or so of the $33 after the parts&labor come out. Sure, shops have to pay overhead like rent/mortgage, insurance, utilities, initial costs for equipment, etc. But guess what? Those are mostly fixed costs that will exist whether you replace that spoke or not.

Those are the costs of doing business, and most every brick-n-mortar business will have similar expenses. To charge a lot of markup is one thing, but to make believe that the markup doesn't exist b/c you gotta keep the lights on and pay the rent is simply dishonest.