The day of the cheap McDonald's hamburger is over. It is the victim of changing demographics in fast-casual restaurants.

McDonald's is busily reorganizing the deck chairs on its ship, sinking into a declining market. Faced with five years of dropping sales, the company is changing its corporate structure into four global segments, selling off 3,500 company-run locations and simplifying its menu.

It's all too late.The day of the hamburger was over back in 1992, when Americans started eating more chicken than beef. Millennials like Panera Bread, Dickey's Barbecue Pit and Chipotle. Baby Boomers prefer a real restaurant.

McDonald's same store sales - 2009 to 2014

Most people think of McDonald's as a place their coach took them after Little League. Or the place that made Morgan Spurlock sick in Super Size Me. Or dinner for the lower middle class.

The marketing lesson

The takeaway here is that you can't ignore changing demographics. Law firms are noticing this as many senior partners retire.

• In 2015, the Millennial generation will surpass the Baby Boom generation as the nation's largest living generation. 
• Millennials are also known as The Net Generation and are internet natives.
• 52% of millennials surveyed said that the technology a brand uses used is the most important factor when making a purchase.

Would you say you are tech-savvy? Or do you still disbelieve that your website can generate new business?

It's time to get active in a LinkedIn group, to write frequent blog posts, to make sure you bio is mobile-friendly, to have a handle on Twitter, to have several videos online for clients, to create a downloadable white paper, to send out a regular e-newsletter...

...or your law firm can wind up like McDonald's.