should there be any following lines after the block, the code without exit will continue to run it (depands on code flow), while the other code with exit will terminate script.

EDIT:
There is no "proper" way, it all depands on "code flow", and if you wish to perform code after that current block, or do some & then just abort anything else.
Likely possible usage to this is when some "critical error" encountered, in a way that you cannot allow to continue any further.