I am no expert on the subject, but I think the kinds of bats that bite humans aren’t looking to bite a chunk out of you. From my understanding, they want to make a wound and then consume the blood.

Apparently, the bites are small enough to often not be visible, so sometimes if you find a dead bat in your house you should collect it to be tested for rabies, as you may not be aware of having been bitten.

Again, not an expert. Almost all of the above was learned by reading Reddit posts back when I went there.