How can I make all folders in Finder "snap to grid"?
The following steps applied &quot;Snap to Grid&quot; even for previously created folders.
Tested on:

10.6.x
10.7.3
10.8.x
10.9.x
10.12.5
10.15.7


Go to any folder control
Control click on the empty space
Click on Show View Options
In the &quot;Sort by&quot; drop down bar select &quot;Snap to Grid&quot;
At the bottom of the window click on the &quot;Use as Defaults&quot;
button

NOTE: Because this will become the default setup for ALL Finder windows you may consider manipulating the Icon size, Grid spacing, Text size, Label position, Background, etc... accordingly.
ALSO: If folders do not appear to have snapped to grid on a previously created folder, Relaunch Finder or you could try to toggle the &quot;Icon size&quot; down and back up too refresh the current window.
This is where it is on 10.15 Catalina: