I guess both have and serve their own purposes!
Wall beamshots
I normally take them to:
- show the pattern of the beam (hotspot, floody, narrow, wide) for indoor use
- compare tints
- show tint shifts
- show effects of different lenses or reflectors
Outdoor beamshots
I normally take them to:
- show the pattern of beam (throwy, wide) for outdoor use
- show/compare how the tints perform in outdoor environment (that has efect not only in colour rendering, but also in distinguishing or not some things in the dark)
- show the range/distance that a flashlight can reach
Some things are better perceivable indoor, against a wall, while others surely stand out in outdoor beamshots. 
EDIT:
I add some examples of what I mean, using the flashlight moded for the OL Contest 2019:
Indoor (and others): MascaratumB’s entry – Old Lumens Contest 2019 - Modified Light Category [FINISHED on 8th February 2020] - #71 by MascaratumB
Oudtoor (and others): MascaratumB’s entry – Old Lumens Contest 2019 - Modified Light Category [FINISHED on 8th February 2020] - #81 by MascaratumB