Tbh, I'm not seeing a huge amount wrong with it.
Given the context of their country, which is completely different to ours culturally with regards to guns, then really the only thing I can see wrong is that he didn't hold the gun with the child. Ultimately he's paid the price for that mistake, but I don't see anything wrong with getting children used to guns as long as you're teaching them a respect for them at the same time. Teach them how to use, how to control, how to be safe, but also teach them that they're f*cking dangerous.
I'd almost compare it to the way that I see no harm in giving kids small amounts of alcohol with meals from an early age, to build up their respect for booze. Shooting guns is fun, no doubts about that, so if you can teach them to do it in a controlled environment then why not?
The issue of whether guns should be as common as they are is another issue entirely, IHMO.