Angled scopes are more versatile.
For prone shooting, with the scope to the side of the shooter, the scope body is rotated in its mount collar towards the shooter, who just turns his head to look thorough the scope.
Same with shooting from a bench.
When standing or seated, an angled scope set at a particular height can accommodate users of different heights without adjustment or strain.
If you ever want to look at the sky, an angled scope will work where a straight scope will not.
The only advantage I see to a straight scope is that it may be easier to locate a target, but my angled Zeiss (like many angled scopes) has a feature to help point the scope at a target with the naked eye, located on the sun shade.