Besides the at begin of scene action is also useful for triggering looping action blocks. I use them often to trigger called by other actions that I've set to loop with the jump to x action part. I use them for dynamically controlling the lighting, opacity, positions & so on of various things in each scene.
As I have mentioned before, a proper save game system should implement a freeze of the current state.
If you have loops going on, they should be reinstanced as they were when the user saved.
Example: if you have a loop of clouds going on in the background that gets called at the start of the scene, a "load" should bring the scene back with the exact position of the clouds and the loop already running, it shouldn't just relaunch the loop from start.
There are ways around this with conditions of course, but I rest my point - a save game should be a freeze, not a global reload of all variables and conditions.