Thing I like about toll roads is that it frees up space on the free roads for us. We found that toll roads in several countries pretty much equal the fuel costs, but of course the argument is - sometimes correctly - that you save time and wear and tear by using the toll roads.
Depends on what you want to do and what is important - the journey or the destination.
We are travellers who are on the road almost every day intent on seeing the country and the people and the culture. Those whose sole intention is to get somewhere without snow and sit in a US-style RV park for several months (Yawn!!!) are probably better off paying the tolls and getting the travel over asap.