It is possible to adapt the symbol dimension to the scale in the layers and the application, services. If you zoom out, the dimensions of the symbol stay the same and at the end you have a very ugly map. Symbol are undifferanciate, one over the other. (here an example from ESRI.... http://www.arcgis.com/home/webmap/viewer.html?webmap=2f5a28f82f4d41ec8dbe6cf96375a970 . The map don't respond to the cartographic standard and give a non professionnal look, a confusing seeing, and a very bad impression to clients.