I do. Who's to say if you use C++, thou shalt always use: smart pointers, move semantics, OOP, templates, and more. Also, you're discounting a very large and very real industry of people writing code for embedded hardware that doesn't necessarily have the luxurious memory resources modern devices have.
Why could I ever possibly want to use C++ if I don't want to use smart pointers and OOP and all that other stuff? Well, generic type safety is very nice. Templates don't exist in C. Constexpr and references are also quite nice. They allow me to annotate my code to make my intentions clearer. Operator overloading is also insanely helpful at times. Matrix/vector math is so much nicer to write/read using mathematical operators instead of function calls everywhere. This also isn't possible in C.
Anyways, don't go making claims that if somebody doesn't use a language exactly the same way you do, then they're using it wrong. Especially when it's a language as massively overengineered as C++. There are plenty of reasons to prefer a subset of C++ to C, and plenty of valid reasons to prefer to use C instead of dealing with the complexities of C++.
In the C++ world I live/work Boost is avoided like the plague. I always wondered how Boost continues to exist, but it seems in certain communities it's held up as a standard to strive for.
Boost continues to exist because there is large overlap with the standards committee and they use it as a staging ground to try out new ideas before they are standardized.