No, they are not. While there are many dangers associated with this creature, bats are actually very beneficial. A few examples of the upside of bats are their benefit to agriculture and humans due to.

Some bats can consume up to 3000 insects every night(½ their body weight) greatly reducing insects that endanger forest and agricultural areas.  As an example, a colony of 150 big brown bats feeding over an agricultural crop can eat 2400 stink bugs in one night.  This reduction in pests means fewer pesticides need to be applied! Bats also reduce the mosquito population.  Another greatly appreciated benefit here in Minnesota.