I agree with you. To expand a little, it's really important to keep the animal's welfare in mind. There are a lot of private zoos and shelters out there with a wide range of quality in animal care and I'm sure many of them are run by people who mean well, but who might not understand the biological needs of the animals they're taking care of and as a result, are unable to give them the best care possible. I'm sure there are many hoops to become an accredited member of the AZA for example, but organizations like this exist for a reason and from what I understand, they have stricter standards than the USDA (which I'm pretty certain is the governmental organization that oversees private animal collections).

This is an interesting viewpoint. Can you elaborate?

Sure. There are a ton of reasons why people shouldn't feed wildlife. The food that we give them might not be appropriate for their diet, it can make them grow accustomed to and possibly even dependent on humans for food, it can encourage abnormal animal congregation that can lead to aggressive behavior (towards people, pets, or each other) and the spreading of diseases, it can disrupt their eating, sleeping, and migration patterns, on and on. Feeding wildlife can easily become a real problem.

With bird feeders and bird baths in particular, I'll just link to the Wikipedia Article on bird feeders and suggest you check out the "Negative Impacts" section. They summarize the point much better than I can and a lot of those same points, especially the hygiene issue, carry over to bird baths as well.