Call me old-fashioned, but when I was growing up in the 60's, every little boy had a smoke rifle, dart guns, pistols that looked like real pistols, and all were used in play... I know, because my baby brother was one of them.
They played cowboys-and-Indians, war type scenarios, cops-and-robbers, and I seen, and still see no harm in such.
The only problem I see... gun crimes are out of control in the USofA, and that's because the States allows every Tom, Dick, and Harry to own a gun, pack a gun, and use a gun, and it set up a culture where guns are gold in everyone's eyes, and so to help offset violent crimes associated with the use of firearms, lawmakers have gone after childhood gun toys, banning this, restricting that, limiting something else, and then there's the following of thumpers that believe that toy play guns and violent video games are to blame for all of the carnage and crimes associated with firearms.
It's all so laughable to me, while at the same time, pathetic. Pathetic, in that young children (particularly little boys) don't get to enjoy the freedom of play as it used to be.
I personally see no issue with any one of those toy things in the link.