This is not a model kit or toy wiki, so such information about accessories in licensed products is unnecessary and would be never ending. A model kit having a stand does not contribute to the Hi-Nu's profile, unless this was a wiki article on the different consumer products available.
That's not necessarily true and is also irrelavent, since the MG Nu Gundam also does not have a place to store its beam rifle on the model kits, yet the MG Hi Nu does. The HGUC Hi Nu removed this ability.
Just because the capability on the product is absent doesn't mean it's absent on the actual machine.
Only the Nu can store its bazooka, the Hi Nu in any grade or scale can't store its weapons anywhere. For example, the HG AGE-FX is missing the hole in the backskirt to store its Stungle Rifle, yet it was depicted as being storable on the backskirt in the show as well as in the lineart.