I would say a large majority of RV'ers do not set up camp in downtown Mexico City, Monterrery, Guarajalara, or Puebla.
And many do not have an inkling of hard info about storage of food.
I haven't seen or talked to a gringo in Mexico in what six months? A year? But family and friends go through intestinal distress just like anyone else. It's just more important with a limited amount of vacation for tourists to avoid it if they can.
I know of no one who has rethought about RV'ing in Mexico because of food worries. Just like I have never heard of anyone cancelling a cruise even though thousands have been poisoned with shipboard illness a hundred times worse than anything I have experienced or heard of in Mexico.
What IS disgusting is seeing RV folks break legs and get electrocuted. "Where's Mary?"
"Oh she has had a stomach bug for the last few days"
Smart people avoid this
What kind of people swear up and down it doesn't exist?
Or recommend seeing a doctor for an Rx of ciprofloxacino antibiotic which can cut down recovery time by 90%.
Or recommend hiring a carpintero to make a wooden box to replace suicide grade metal stairways that hurt the elderly.
I had tennis shoes with felt glued to the soles (GOOP) for use on slippery cobblestone streets and slimy Mayan temple temple knee high half shoe length stone steps.
Paranoia or intelligence?
Low IQ people alarm prospective newbies with tales of disaster.
High IQ people tell newbies how to minimize risks with simple work arounds.