https://developers.google.com/maps/terms
10.1.2(a): "You must not charge users or any other third party any fee for the use of the Maps API Implementation, the Service, or the Content ... "
You can use it on a commercial site, but the maps implementation must be available to free users. It limits your options but there are plenty of sites that are commercial ventures and work within these limitations.
You can use it on a commercial site, but the maps implementation must be available to free users. It limits your options but there are plenty of sites that are commercial ventures and work within these limitations.