Based on the horror you have presented, I think it is imperative that Montana outlaw diy by all non-Montanans ASAP. In fact, every state in the U.S. should take immediate action to protect it's resources from the arrogant, trash throwing, economy killing, society destroying Americans - other than the perfectly behaved residents of their own state of course! Only the pure of heart who are willing to hire guides can be trusted it seems.
The truth of the matter? Such behavior is a characteristic of an individual, not a chosen style of fishing, nationality, group, or location. Arrogant pigs will still be arrogant pigs, whether they are alone or with a guide while they are on the water - or whether they are in the Bahamas or on the Big Hole during the salmon fly hatch. What needs to be addressed is the inappropriate behavior and specific problems where they exist. Implementing a license requirement that generates revenue to establish laws and put wardens on the water is the correct direction. Not a law that severely impacts the overall economic well being of the Bahamian nation for the benefit of a few. Don't kid yourself - it will. Diy fishermen will abandon the Bahamas not because diy fishermen are inflexible or blindly self rightous - most diy fishermen I know also hire guides at times. Fishermen who diy do so generally for two reasons. Diy allows those with limited finances the opportunity to do something they otherwise couldn't, or do it multiple times instead of very, very occasionally. More importantly, at least for me, is the diy experience. The fun is in the exploring of new places, learning the area and fish myself, hunting and then spotting the fish myself. Actually catching a bonefish is great fun, but somewhat anticlimatic. It's everything else leading up to the catch that makes bonefishing so addicting. It certainly isn't the total catch count. Given the true motive for most diy fishermen, there is absolutely no reason that they (I) would continue to fish the Bahamas if a guide were required (at least at anywhere near the frequency they do now). In fact, if I were to return to the Bahamas under guide required conditions, it would be primarily to visit the friends I have made.
Having had my say, I am just eternally grateful for the opportunities I have had, the people I have met, and the places I have experienced. And, I feel quite blessed that I haven't encountered any of the horror you describe.