The value of the service (outfitter or guide) is what is supported by the market. Whether we as individuals can afford that is based on our circumstance and priorities. As soon a tip becomes mandatory or a set price is determined; it becomes a fee for service, not a gratuity. Gratuity is a self determined amount to show appreciation. One thing to consider about guides and how much they work is that many (not all) do some scouting with or even independent of the outfitter. It is time consuming and requires fuel, supplies, etc. I expect it is rare for them to get paid for that.