No, there are may ways of holding tomatoes up off the ground. The big indeterminate cultivars can grow 8- 12 feet tall and really need some type of support. People prune them to a single vine and tie them to 6 ft. stakes, others run an overhead wire and tie them up to that, some build elaborate trellises. You name it, it has probably been done. Lots of folks especially commercial growers use the short bushes indeterminates and either use short stakes or let them sprawl. Cages are my choice, because they are easy to use, and I don't prune. Six foot concrete reinforcing wire makes the best cages. A 6 x 6 ft piece makes a nice cage.
A caged Park's Whopper