Scam, don't show them your bill.

When I first moved to Baltimore, they had a polite female student-type come to my door to talk about clean energy. I stupidly showed her my bill and she immediately signed us up to a 3rd party provider! We called the company right away and managed to cancel it.

These days, I never open the door to anyone, it's hard enough to get actual BGE people on the line when you need them.