I'm sorry this practice left a bad taste in your mouth and I hope I don't come across as a smart mouthed punk or start a fight but here is my take...

I assure you that if the guide/outfitter supplies any flies, leaders, tippet, etc. they are charging you for them. If they don't take inventory at the end of the day and charge you for the individual items, they have already factored the cost of these items into their guide fee.

Put another way, we all pay for these types of things in everything we do. The grocery store has factored in the price of grocery bags into their prices, the gas station has factored in the price of the paper towel you use when you wash your windshield and the person you hire to build your deck is charging you for very nail and screw they use. Sometimes those costs are buried in the total cost and sometimes things are itemized.

I guess I would rather a guide charge me for every fly individually instead of burying that charge into their fee. What if they automatically factor in the cost of 12 flies and I only hang 6 in a tree?

Just my 2cents worth.