There's more at stake here than whether Disney has a right to make a corporate profit.
Zoos have to support themselves, but they exist to be zoos, so if their activities go against their Mission than there's no reason for anyone to support them.
The attribution (or imposition) of "humanness" to animals certainly cuts both ways. Yes, it can inspire love and interest, but also leads to the "Bambi syndrome" of which animal rights extremists represent the worst offenders.
This is a fascinating and important issue.
Zoos would do well to study this issue and determine what value, if any, it has to them.
I can see with my own eyes that connecting live animals to fictional anthropomorphized characters does get the attention of children and families.
But what I'd really like to know is, does that attention ever connect to conservation issues or action?
If all it does is make the zoo-visiting children scream louder, but it does not instill any sense of protecting the environment, then how has it served the zoo's mission?
If it instead supports the faux-Nature imagery that is shown in a cartoon and thus inhibits true ecological understanding in the visitor, then I think it works in opposition to the zoo's goals. (What does Pumba teach us about warthog ecology?)
I'd love to learn of any studies on the effects of cartooning the zoo animals on the public's perceptions.
I'll have to find this article:
http://muse.jhu.edu/login?uri=/journals/theatre_topics/v017/17.2scott01.html