It's possible that there are more 1911s out there that are "owned". I've often considered Glock to be a "gateway gun".
I would wager that there are many people who make the Glock their first firearm purchase for a number of reasons. They get recommended often because they are relatively low maintenance for first time shooters or people who are buying only one firearm for defense. These people can't be bothered to properly maintain a firearm such as the 1911, and sometimes not even their Glock.
Also people may be interested in Glock for the first firearm because they know law enforcement also carries Glock and they figure if it's good enough for LEOs it's good enough for them.
Now with 1911 owners you can expect that more than likely they already have prior experience with firearms and have a better understanding and practice of safe handling of firearms. I'm not implying that the 1911 is NOT safer, just that the likely owners of 1911s are statistically more likely to handle them in a safe manor.
Also 1911 owners are notorious for owning multiple 1911s. Yes, there are Glock owners who have multiple Glocks (myself included), but I know that the eventual outcome of my firearm collecting is that I will own multiple 1911s.
There are exceptions to all of this I'm sure, but I believe these AD/ND situations come from lack of experience and/or general negligence that would be avoided if one practiced safe handling of firearms.