Andrew,

I have used guides in the past that charged me for the flies I used, and they didn't even give me the flies. Others have had me purchase flies for the trip from their fly shop. That is all right but I prefer not to do it that way. Now days, the guides I use are the good guides. They cover the cost of the flies and tippet and split shot when nymphing, etc. For those guides, I make sure I give them a very healthy tip, they deserve it. As for the other guides who use the practice you mentioned, my tipping would really be on the minimal side. Always have a clear understanding with the guides and fly shop/outfitter as to all expenses they expect you to pay. Ask them up front so there are no surprises.

Larry ---sagefisher---