Sure, but neither do binary searches and balancing trees. If writing a 10000 line game is not like working on a million line project, writing a 100 line algorit

Sure, but neither do binary searches and balancing trees. If writing a 10000 line game is not like working on a million line project, writing a 100 line algorithm is even less so. And yet, some recruiters value coding tests more. In fact, practices in competitive coding are almost the opposite of what you need in large projects. You need to get a result as fast as possible, and the code is thrown away in the end. Readability, robustness, reusability, none of these matter, descriptive names are a waste of time, so is freeing up resources. Competitive coders are usually good coders in general, simply because they care, but so are people with side projects.