If you ask a skilled professional to do menial trivia, expect to pay for their skill level.
Yeah an inner tube for $35? And it's not even those fancy orange ones?
Well it's not hard to change it yourself, as long as they're not charging more than $4 for a basic ones. If they are actually selling it for $35 that's pretty yikes. I'd just buy it online given that it doesn't benefit from retail (you don't need to see a tube in person, just need to know the dimensions)
Bike shops need to charge for labor because most people don't buy bikes from bike shops anymore, so labor is where they make their money. $100/hr for labor is on the higher end but doesn't seem crazy in expensive locations. Not to mention that the prevailing way people treat bike shops (as places you can walk in at any time, get your bike fixed, and walk out) is incredibly antithetical to bike mechanics actually being able to take the uninterrupted time to focus and do good work.
You don't seem to respond to those things.