How to reproduce:
1. Create and open a new project
2. Install the ProBuilder package from Package Manager
3. Select the “Create Shape“ Tool from the Scene view Tools overlay
4. Select “First Vertex“ for Pivot in Shape Settings overlay in Scene view
5. Place down a Cube in the Scene view while holding Shift
6. Change the “Tool handle“ to “Pivot“
7. Observe the pivot point of the Cube in the Scene view

Expected result: Cubes pivot point is on one of the vertices
Actual result: Cubes pivot point is at the center of it

Reproducible in: 6.0.1-pre.1, 6.0.4 (6000.0.28f1, 6000.1.0a5)
Not reproducible in: 5.2.3 (2021.3.46f1, 2022.3.53f1, 6000.0.28f1)

Reproduced on: Windows 11 Pro (23H2), macOS 11.7.10 (by the reporter)
Not reproduced on: No other environment tested

Note: Not reproducible if the Cube is created without holding Shift