Moose are eldrich guardians of the ley lines and handle code inspection for the Realm of Faerie.
If one trashes your deck you probably violated the Seelie/Unseelie Harmonized Residential Code(if it’s your business’s deck the Harmonized Building Code).
This is why the more professional moose will have dimensionally standardized antlers, since it’s very hard to use an ell*-wand to verify dimensions when you are a quadruped with no hands.
(Edit: this is why you should never use the phrase “You call those NIST traceable?” in reference to a moose’s antlers. They don’t take those sorts of accusations well.)
*Yeah, don’t ask about ‘ell’. Normally it corresponds to one of the archaic customary units of length in use by a given region’s inhabitants at the time local Faerie code was last updated; but there are exceptions(the region around Paris where radical Jacobin pixies redefined it to equal the 1793 meter and built a lot of particularly Sylvan guillotines is the best know counterexample; other cases tend to crop up where major human population flows have modified the distribution of Faerie populations as well, a common case in the new world).
The new world case is particularly tricky because all the moose will tell you is “the ell is as the code was written” or “the ell is inscribed upon the old bones”; and because the relevant customary units of precolumbian populations are rather obscure, since colonization hit them very hard; and in some but not all cases they’ve been supplanted by the ell associated with the major colonizing group’s region of origin.
All this makes it even harder to know if your deck’s railing has the required Fey whimsey per ell, falls within the keep-out region of an ancient one’s ley easement; or violates some particularly dickish bylaw of the nearest gnome HOA. Being baffled by moose behavior in these situations is really pretty understandable.