It ain't the gun, it's the gunner . . .
Sounds like insecurity and immaturity with a side of bad manners. I wouldn't dis someone's choice of firearm out of hand. One man's meat is another man's poison, we've all got to live within our means and sometimes make do with what we've got. I let my targets do my talking, and it seems to work out that somedays you give lessons, some days you take them.
In virtually every field of endeavor I've dabbled in there always seems to be a class of person who tries to substitute money for diligence, discipline, and perserverance. Rather than take the time and make the effort to become thoroughly familiar and well practiced with their gear, they go out and buy a more expensive "better" one when whatever they've got hasn't turned them into a top contender. A fool with a tool (regardless of how fine a tool), is still a fool.