How to disable places on google map V3?

Just a pointer - this seems possible with custom styled maps. If I'm not mistaken, the feature type you're looking for would be poi.business, whose visiblity you would turn off.

There's a wizard to help you build the options array.

You can remove it by adding the following code:

var styles = [
   {
     featureType: "poi",
     stylers: [
      { visibility: "off" }
     ]   
    }
];

var styledMap = new google.maps.StyledMapType(styles,{name: "Styled Map"});