You don't need codes to remove the Google Maps feature. If you leave the Google Maps API field blank in the ClassiPress admin dashboard, the map simply won't appear.
The street name and any other location fields can also be removed using the ClassiPress custom forms and fields feature, so this does not require any hard coding.
You can see the side by side comparison here on the
ClassiPress features page, but with the release of WordPress 3.0 and recent changes to our licencing, no there isn't much difference now.