I don't think that animals should suffer for our enjoyment.
Just my thoughts. Why didn't they use rubber bats?
Bats are such great creatures. Each one eats about one ton of bugs a year. Rats are great too. Rat spend 90% of their time cleaning themselves. They're really very clean by wild animal standards. It is human soil that makes most of the dirty when we see them.
They make much better pets than gerbals or hamsters. More social, more intelligent, (intelligence of a 2 year old child) and are easy to raise.