You probably don't need vectors to describe behavior along a one-dimensional line (scalars will do just fine for that), but if you are going to handle multi-dimensional objects then you are going to need to use vector math to track the given values along each separate axis. For example, for a p-orbital, you have to specify values along each of three spatial dimensions to describe its spatial relationships accurately (since a p-orbital manifests itself as a three dimensional object when visualized).
There are basic quantum mechanical problems used to introduce the topic that avoid vector math, such as the one dimensional particle in a box problem, but these problems lack reality. To get a more complete description of a p-orbital the mathematics are necessarily more complicated.