Speaker wire/cables opinion

I have some decent speaker cables in my system running from my McIntosh MC601 mono blocks, and audio space EL34 tube amps to my speakers. But I started to think, should I spend more for speaker cables when I don't really know the quality of the cables that goes from the speaker terminals to the speakers? For all I know they might be lamp cords connecting the speakers. I have never seen it anywhere, where the speaker manufacturer disclosure what type of wire they use. Can you imagine paying over $2K on speaker cable to find out they are connected to lamp cords that wire the speakers? I wish we could buy our own wires to connect the speakers internally (am I on to something here?). This would ensure consistency in the speaker chain. Probably that's why people and reviewers (not people=cats and pooches) say cables sound so differently. The internal speaker wires could be the "weak link". I am inspecting my speaker to see if I can get to the internal wires. What are your thoughts?