How to reproduce:

1. Open attached project "858899-repro.zip"
2. Open "entry" scene
3. Set Snap Settings Move X, Y and Z to 0.25
4. Select "sprite_unsnapped" and "sprite_snapped" Game Objects in the Scene View
5. Hold the Control key (Command on Mac) and move selected objects by dragging the position handles
6. Check if "sprite_snapped" position x and y are still snapped to 0.25
7. Zoom out the Scene View
8. Repeat 4-6 steps

Expected behavior: position values are snapped to 0.25
Actual behavior: position value of e.g. 7.25 is 7.3 or 7.75 is 7.8

Note: It happens not only with 2D Objects but also with 3D Objects in X, Y and Z axes

Reproducible: 5.3.7p2, 5.4.3p3, 5.5.0p1, 5 5.6.0a6, 2019.3.0a12