I think everyone agrees that having a deep understanding of calculus is extremely helpful for many applied fields (physics, engineering, comp sci, etc.). But why does this not also hold for variational calculus?
There are a few fields in physics that I know of that use variational calculus as a starting point to derive a few important equations, but a deep understanding of variational calculus is considered to be unnecessary. For instance, "Lagrange equations of motions" in an advanced classical mechanics course are often derived without going into a more general theory on the idea of minimizing functionals.
Optimizing functionals seems to me to be a very powerful tool for things like nonlinear optimization, yet I find it to be extremely rare to come across anything that actually uses it practically. Is there a reason why this is the case? For example, maybe other techniques (genetic algorithms, monte-carlo simulations) are more practical?