I have traveled in ALL of the northeast / mid-atlantic states many times. When you see a sign that says "Service Area" what one normally finds is a large area with parking for cars and buses, a grassy area for dog walking, picnic tables, plenty of bathrooms and depending on how the Service Area was marked, there might also be a gas station, restaurants and a tourism center. Sometimes even a geocache! (ahem) :-)
However, If you are travelling along the Garden State Parkway in NJ (in bumper to bumper beach traffic no less) and you have the misfortune to stop at a "Service Area" near exit 129 you will find two gas stations, hardly any parking and a couple of FILTHY BATHROOMS at each of the gas stations - NAMELY SHELL AND MOBIL that are supposed to accommodate the 300 million people travelling on the GSP. I waited on a long line to use the bathroom at SHELL and it was the MOST DISGUSTING BATHROOM I have used in recent AND distant memory. We ended up walking over to the ON THE RUN MOBIL to get something to eat and even the trash can out front was OVERFLOWING with GARBAGE. This "Service Area" was in no way big enough to accommodate the volume of travelers on this highway and it clearly isn't staffed well enough to even keep the bathrooms cleaned or the garbage emptied. SHELL, MOBIL AND STATE OF NEW JERSEY, YOU SHOULD BE EMBARRASSED THAT'S WHAT YOU HAVE TO OFFER TRAVELERS IN YOUR STATE.