Pretty much what the others said, stick to the established. I only had one person come to my door since I moved in in May, about (and I'm paraphrasing/trying to recall) "PECO doing something new and making sure it shows up on my bill" -- I said I'm not sure but I'd get a bill shut the door, never came back, and they left and never returned.

Basically if anyone comes to your door regarding utilities, don't answer it. I mean there's really no reason to answer your door unless you're expecting a package. Don't know if physical mail about this ever comes in, I've only gotten scam deed/home insurance things through USPS.