B-b-b-but ALF/ELF always claim they make sure a building's empty before they torch it.
They also don't give a rat's patoot about the firefighters who put their lives and safety at risk fighting the arsons.
When they are arrested, they're indistinguishable from the folks who show up at ANSWER rallies.
They make sure there are no creatures in the building. For them, that means plants and non-human animals. Provided they are large enough to be visible.
It's like the "anti-discrimination" people. No person must be discriminated against, where "person" is a woman or a non-white, non-disabled etc. man.