When did “large, bureaucratic telephone company” become “Bay St.”?

Star today: How I lost my Bay St. job and found true happiness

It’s a familiar story — to me, at least:-) Girl gets MBA, pursues high-paying job, is laid off/gets a bonus that makes it easy to walk away, soul-searches, finds lower-paying dream job. OK, her story has a Marley-and-Me-esque dog involved. But let’s be clear: working in marketing at Bell Canada, while undoubtedly soul-sucking, is not “Bay St.”, e.g., the capital markets. Is it the Star’s mislabelling or the writer’s?