how to Indicate frequent flight routes when booking flights

I'm designing a flow that will reduce the likelihood of users getting zero results when they search for a flight. When looking at examples of how other airline apps do this, I came across the following example (scoot airlines app).

I'm trying to figure out if the black airplane icon is an indicates more common flight routes. I find it's not very intuitive.

What would be a better design approach to execute this solution?