Can certain areas actually drain batteries faster than other areas? I never experienced an investigation where batteries drained at all, and on one investigation in May, we had 8 devices that lost charges within 5 minutes of installation. Various battery types (lithium, standard, and in unit rechargeables all failed without warning very rapidly). Perhaps when these drains occur it's the location rather than entities.
I can tell you that the house we investigated is near my home...the entire area near and around my house is built atop a large mass of glacial granite deposits, with several natural springs in area. Maybe the area is producing a field of some type naturally that is creating stress on batteries? It's worth noting that in my own home, I've never had a problem with battery drain.
I am not aware of any way any natural location can cause battery drain. Possibly in areas of extreme RF fields, etc. such factors may come into play, but the fields would have to be orders of magnitude greater than any we would encounter unless you stood directly in front of a radar antenna or something like that.
Regarding areas placing stress, that should be repeatable. My recommendation would be to set up a controlled experiment in such a suspect location and conduct tests. If a pattern could be established, then further research may reveal exactly what is present that causes this effect. From there more research may open new avenues for study.
But I don't ascribe any such power to spirits without seeing some more concrete proof. As I said I use a power module for my research which allows nme to keep tabs on my power drain and I have never experienced any abnormal effects in 30 years of research.