This is a great use for a old toddler runner. You can tell from the set up of the two guns this is someones setup they use at 3 gun competitions. The rifle has a flared mag well. Very common on competition guns. Also the shotgun has a extended mag tube. That also points to this being someone competition guns. Then you have the bag in the seat which likely has his ear, eye protection ammo, and medical supplies along with the handgun which is used in the 3 gun. Most likely a 1911 though some like to use a glock for 3 gun.

Here is a link to anyone who doesn’t know what 3 gun is.