I don't think there will ever be a resolution to the problem of bait fishermen & poaching in the park. Post the laws & change the regulations all you want, but when it comes down to it, the park is never going to have enough money to provide the manpower for effective enforcement. With the park being the most visited park in the country, it starts to boil down to a priority system. So little time and personnel, with so much traffic, several large campgrounds, children's programs, other rules & regulations to be enforced, and so on and so forth....park personnel have to determine what is priority, and I doubt searching the river banks for anyone who might be using an illegal method of fishing is very high on the ole' Totem Pole. It's just one of those crappy things that we have to deal with.
There is however a few things you can do to make yourself feel better about the situation. Every time you go to the park, forget about the bait fishermen, your job, politics, finances, or anything else that bothers you during your everyday life. Look at your surroundings and think about how great your country is and how fortunate we are to have such a beautiful place to spend our free time.