Is there any reason I don’t see this in C++? Is it bad practice?
No. It is not a bad practice, but the following approach renders your code certain flexibility.
Usually, pre-C++11 the code for iterating over container elements uses iterators, something like:
std::vector<int>::iterator it = vector.begin();
This is because it makes the code more flexible.
All standard library containers support and provide iterators. If at a later point of development you need to switch to another container, then this code does not need to be changed.
Note: Writing code which works with every possible standard library container is not as easy as it might seem to be.