Physicists are going to object.
First, the process of increasing entropy is not the same as entropy itself; entropy is just a characteristic of the system. Statements such as "Entropy made this process occur," for example, invite misconception. It would be more accurate to say "The tendency for entropy maximization in the universe made this process occur." Again, the state function of entropy is not the same as the tendency for entropy maximization.
(In fact, if chunks of the desert and the beach contain the same volume of the same sand and the desert is hotter than the beach, then the desert system would have a higher, not lower, entropy because entropy for a simple system at equilibrium increases with temperature.)
Second, the speed of corrosion is a kinetics problem, not a thermodynamics one. Corrosion is mediated by how fast water vapor diffuses into the area, among other parameters, which has little to do with entropy (except inasmuch as entropy maximization of the universe drives every spontaneous process).
If I could change your system slightly from corrosion speed to oxidation (i.e., rusting) vs. reduction (i.e., turning ore into a pure metal), we could discuss one way that entropy and entropy maximization affect us worldwide on a daily basis. This example is widely discussed in textbooks and is useful for firming up your understanding of these concepts.
Although it's true that entropy always tends to increase in a closed system, things are different in our common surroundings of an open system with constant pressure and temperature. Here, the quantity $H-TS$ tends to decrease, where $H$ (termed the enthalpy) is largely a measure of bond strength, $T$ is the temperature, and $S$ is the entropy. If bonding isn't involved, then a decrease in $-TS$ essentially says that we're back to maximizing entropy.
The quantity $H-TS$ is negative for all spontaneous processes at constant temperature and pressure. Rust is a more stable compound than iron; its $H$ is lower, and so at lower temperature such as room temperature, rusting proceeds spontaneously. However, a consequence to rusting is that oxygen is turned from a gas into a solid (iron oxide), which causes a decrease in entropy. As a result, at higher temperatures and in an oxygen-scarce environment, $H-TS$ is negative only if the reaction runs the other way: rust turning into iron. (In other words, entropy maximization has won out due to the presence of the $T$ coefficient in the $H-TS$; the spontaneity of the forward or backward reaction can be visualized using an Ellingham diagram.) This is one of the ways that civilization obtains metal from ore.
So this is a quick example of a description of entropy and entropy-driven spontaneity that physicists (and engineers) would be on board with.