This is a load of crap. Why do people who no nothing about guns whatsoever insist on blaming the gun laws? To begin with, what supermarket does he shop at? I've seen to many and all I've seen are knives and the occasional low powered airsoft gun(at least around here).
As for the effectiveness often cited with the near total ban of firearms in the UK, with the exception of murder and rape, they top us by a considerable amount. In fact, you are 6 times more likely to get mugged on the streets of London than the streets of New York. Roughly half of the burglaries occur when the homeowner is home, whereas in the US, only 13 percent happen when the homeowner is home, mainly because homeowners are far more likely to own a gun in the US.
Sticking with the New York-London comparison, though New York's murder rate is nearly 6 times higher than London's, it has been like that for nearly 200 years, and crime rates in both cities actually spiked whenever gun control laws were enacted. When you lower gun ownership rates, you get drops in accidental firearms deaths, but to disarm law abiding citizens for this reason is tantamount to calling them idiots who cannot be trusted to use a gun safely.