Years ago, I learned (the hard way) to always find your actual gate at the airport before you settle down to wait for your flight. I was 22 and on my first business trip. I was heading out of Gate 23 and had some postcards to write, so I sat down by the mailbox (There used to be such a thing within the terminal. Really!) at Gate 22 and waited for them to call my flight. They called, I popped up, and found out that Gate 23 was a tram ride away from Gate 22. It was sad.
Since then, I’ve always made it a point to get to the actual gate first, then eat, shop, whatever. This has paid off many times. (OK, once in Orlando I told this story while not following the same advice (how ironic!) and missed the concept of a monorail to the gate and almost blew it but I almost always made a point of this..)
Sally tried to follow this advice, when she was early for her flight. She went through security with more than an hour to spare, planning on buying dinner for the flight, and then found out that the area had pretty much nothing. All the food was somewhere else. So sad!
So the modified lesson is: Find out where your gate is. Find out if there are the services you need. Make an informed decision based on the sum of these parts. But still please leave some extra time in case there is an unmapped monorail in your future.
Jane's Lessons Learned 
This reminds me of a Loius CK skit where he gets off the plane and goes and eats a Cinnabon.
And never assume that if your plane switches gates, they’ll tell you.