I guess you could. I've never used them interchangeably, so if there is an issue I don't know what it would be, but I bet there's a reason why people use them for their own corresponding scenarios. If you decide to use one instead of the other and find why that is, report back.
Fun fact,
If you have a Cube (or any Mesh Object) Selected in Object Mode and hit CTRL+5, Blender Adds a Subdivision Surface Modifier of Level 5, as you know, but if you Have a Cube (any Mesh) Selected in Sculpt Mode and press CTRL+5, Blender Adds a Multiresolution Modifier of Level 5.
Both Modifiers can be used, they are very similar, but the Subdivision Surface Modifier has to be Applied, so it is more 'destructive' in a way.
But, Dynamic Topology and Remesh cannot be used together with a Multires Modifier.
Multires uses more Memory(RAM and Virtual RAM), because it has to keep vertex information for each level. Also multires isn't affected by the simplify settings. It also has the Linear subdivision option and is designed with sculpting in mind. The default subdivision uses a slightly different smoothing options which can lead to faces not always being evenly smooth after the faces are divided, which is useful for sculpts that have convex to concave switching. Subsurf will make sharper creases. Most of the time they work exactly the same an both use the Pixar OpenSubdiv libraries.
Basically, yes you could use multires instead of Subsurf.