Most of the violence perpetrated with guns in Mexico is NARCO VS. NARCO and not that much against random innocent victims, out of 100 murders 90 are committed by narcos against other narcos for control of territory or drug routes, the remaining 10 are your standard murders of passion and robberies gone wrong or carjacking's that the owner has resisted instead of just handing the keys and or purse, you have more innocent persons being gunned down in the US than in Mexico, most of the murdered persons and therefore the statistics are related to persons involved in the drug trafficking, bad guys and innocents are all lumped together at the end in a number, regardless of who they are.
One has to remember that Mexicans are hot headed and have very short fuses, couple that with alcohol and add a gun and you have total chaos, it is bad enough that they have cuchillos (knifes) and really sharp machetes, you do not want them armed with a gun, I can deal with a knife or a machete but not with a gun that easy.
So no, having lax gun laws will not help in Mexico at all, as a matter of fact the police and army conduct random checks that focus on concealed weapons and you can only purchase small 22 caliber guns for home protection at special army stores with a one time permit to transport the weapon to the house, it is nearly impossible for a regular civilian to obtain a concealed and carry permit, unless you know or have someone in the government.
As for the Canadians and gringos travelling in RV'S you are actually safer in Mexico than in the US, the bad guys do not want to interfere with the turista, it brings to much attention to them from the press and from the government agencies, that is the last thing that they want, as for simple robberies well you will also be mugged in Canada and the US as you will in Mexico, that happens all over the world, give the perp an opportunity and you're it.
Some years ago in Texas they allowed the narcos to purchase weapons from arms dealers with out to many restrictions, they wanted to trace where the weapons ended, the last operation was out of Phoenix, Arizona run by the ATF they called it Fast and Furious, it went down the drain as fast as it started, they lost track of all the weapons and some ended in Texas, that is how the narcos got a hold of some pretty powerful sniper rifles and ammo, 2,000 weapons some have been recovered, Mexican Government was not informed, they found out when the news papers ran the story, today most of the illegal weapons enter trough the border with Guatemala, Swiss cheese has les holes than that border, that is how they got hold of RPG's one was used to bring down a police helicopter, some of drug lords have gold platted AK 47 rifles and 45' hand guns and 9mm guns with ivory handles, some are really nice and fancy.
I will repeat as an RVer travelling in Mexico you are safer than in the US, I can not speak of Canada because I do not have info on that, I have only been in Gander at the airport while the aircraft was refueled for the hop to and from Europe.
Some of the foreigners that have been murdered in Mexico at the end of the investigation it has been determined that they were involved with narcos in one way or another, yes there have been others that got killed but they were a crime of opportunity more for robbery than anything else.
So as a turista in Mexico with or with out an RV you have a safe pass card, just do not do anything dumb.
navegator