In Rust, you often use stack allocation, which, as you pointed out, is much more efficient. There's some heap allocation in Rust, but in my experience it's actually a minority of all allocations.

Rust also has an Arena library (http://doc.rust-lang.org/0.11.0/arena/index.html), which can be used for cases where you know that you have enough memory for a given operation and are willing to throw out the entire thing when the operation (or program ;) ) is done.