The key thing about the
Electra Townie and bike carrier racks is not its weight--although that's considerable--but the swoopy sloping top tube. It's not really going to work well on trunk racks, which are designed to hold the bike by the top tube. Or even hitch racks that hold it by the top tube. Yes, with adapter rails and futzing, it can be made to work, but life's too short.
You need a rack that holds it by the wheels. Given the gravity in Townies, hitch racks are your best bet. This past spring I bought a
Yakima Holdup. Saris, Thule and others make essentially similar models. I was able to get a better deal on the Yakima.
There are cheaper models out there, but this type of rack seemed to be right for me. It's easy to use, folds up out of the way when the bikes are off, and of particular note, you can lock the rack to the car, and lock the bikes to the rack, which is handy when stopping to eat on the way, or on the way home.
The manager of my LBS -- who is quite experienced and knowledgeable -- very much agrees with you and, in fact, that is what he himself uses.
BTW though, I lock my bike on my car even though I only have a Saris trunk rack. I use a 6foot cable lock and under the car bumber is a ring that I thread it through and then up through the frame of the bike. It's not long enough to secure the wheels, but I only use it for short stops in a store or in other public, well travelled areas... But, it does mean that I can stop on the way home from a ride and even run a few errands without worrying about the bike being stolen.