Have to totally agree with you here. I own 5 dogs and though I hate leaving them when I go on vacation, taking them to WDW is not in the cards. As someone who works in the animal field, you can totally see how people would bring their pets to the resorts, it would either get lost or stolen or get out during housekeeping (not to mention..how many dogs would let the housekeepers in while they're stressed out, sitting in a hotel room by themselves). Next you'd see those with the tiny, purse-sized dogs taking them into the parks and tragedy would eventually strike as little "Fluffy" dies of a heart attack because her dippy 16 year old owner thought it would be fun and cool to take her on Mission Space or something similar. You KNOW this would eventually happen. Also, with the amount of children running around in close proximity to swimming pools, someone..you know it will happen..will not pick up after their dog and it would just become a mess. You may not do something like what I stated above...but you know darn well someone will.
Pets belong at home with someone looking out for their best interests.