I'd like to appologise in advance for the length of this reply :P
I think comparing bird of prey shows and marine shows is a little like comparing apples to... jumbo jets.
Raptors (birds of prey) have been kept in captivity, mostly for falconry, for hundreds of years. Their requirements are fairly easy to meet in most situations, and are generally well-known. As someone who works with captive birds of prey, I can assure you any good falconer or flight show trainer would quit before submitting any bird to unsafe, unsanitary or unhealthy situations, and take great pride in the health- both physical and mental- of the birds in their care.
In the past few years, outdated training methods have fallen somewhat out of favour. Many places are starting to use more ethical training methods, such as positive reinforcement, instead of the "old school" falconry training which could be very stressful on the birds.
Additionally, almost all show birds are captive-bred or imprinted, or are otherwise unreleaseable (exotic species, etc). Captive breeding has been a great boon to the bird of prey world; the only reason peregrines still exist in my part of the world is by captive breeding, rehabilitationa nd release programs- funded by bird of prey demonstrations or "shows". Many other not-for-profit organizations can thank flight demonstrations for their continued existence, particularly many wildlife rehabilitation centers and raptor conservation centers.
In contract, marine shows feature animals whose needs are almost (if not totally) impossible to meet properly in captivity. Additionally, many marine show animals are still wild caught. While marine trainers are one of the fore-running groups supporting the use of ethical training methods, the ethics of keeping such huge animals whose actual needs are not truly understood is somewhat... fuzzy, in my opinion. Additionally, most marine mammals rate much higher on the intelligence, activity and social scale then your average raptor; which mkes animals such as killer whales and dolphins much harder to keep "happy" in captivity. Additionally, I am unaware of any not-for-profit organization using marine shows to garner spport for rehabilitation or conservation. For more information on the aquisition of marine animals for "shows", I'd highly recommend the documentary "The Cove"- but only for those with a strong stomach.