Change Awesome Icons?

The awesome icons in the Service section are not customisable from the themes panel. I’ve noted on the example sites given in this support forum that they have resorted to removing them entirely.

In Firefox, I can select Inspect Element to see the HTML reference, which is:
<i class=”fa fa-wordpress”></i>

I can change this live, for example to:

<i class=”fa fa-camera-retro”></i>

and I see the camera icon instantly updated.

However, I cannot find any physical reference in the theme files referring to these icons and I assume they are generated by the javascript and bootstrap files when running in real time.

Is there a way to change these icons to something more suitable.

Thanks for any assistance.