"Credit cards are not accepted here."
I suspect it doesn't have a literal subject. "Here [they] don't take credit cards." You can compare it to these sentences I found on tatoeba.org:
这里不能停车。"[You] can't park here," not "This place can't park cars." 这里无法呼吸。"[One is] unable to breathe here," not "This place is unable to breathe."
I checked a few dozen sentences and didn't see any where 这里 is unambiguously a subject.