Yes. For the items they carry they are generally much cheaper. They minimize all unnecessary costs like marketing and packaging, encourage self checkout and using your own reusable bags. Their stores are spartan and they sell box/can goods right out of bulk/pallet packaging so that also saves some logistics cost.
I live in a HCOL area (for the Midwest anyway) and while you can’t get everything at Aldi, you’d pay 1.5 - 2 times the price buying similar food at a regular regional supermarket. You’d probably pay 2 or 3 times the price if you did all your shopping at a Gucci place like Whole Foods or Sprouts.