It all depends on values, if there is physical harm being done to something, and it's unlawful then yes, report it, but don't push your beliefs onto the person.
As long as they are not pushing their beliefs, and not doing anything unlawful, then just ignore them. That's why law exists, to deem what is ethical, and what isn't. It helps us to define the line between what is okay to do, and what isn't.