Markeytmaker....
Are you wondering for it to have been like that from the manufacturer or, as a conversion??
The figures all have some point where they are stuck to the base and then the bottom of the base is repainted over them so, it is very easy to remove the figures from the bases. Removing the gun from the sand bags would also be quite easy and would not cause real issues just a small sanding after removal and little touch up.
You would have to ask the manufacturer if its not a conversion question
Mitch