I have done probably more than 1,000 inspections of restaurants, food truck operations, and convenience stores over the years and as mentioned above, you probably would never eat out in at least half of the food establishments if you could be a fly on the wall for a few days.
Just in the short period of time I have been in a commercial kitchen I have witnessed food preparers scratching their skin, brushing back their hair, picking up food accidentally dropped on the floor and just picked up and used while handling the food before and after cooking it.
Having said that, some of the convenience stores are the cleanest there are. There is not a relationship on whether a restaurant is a national chain, franchise or locally owned or what type of food establishment it is on whatever on the care and cleanliness of the operation. It all begins and ends with the care of the management and employees.
The worst case I ever saw was an operation, not in Brazos county, that was a three vehicle Mexican food vendor where three women were preparing dozens of tamales under an open old wooden carport on rough tables with about ten thousand flies flying around and landing on the food before being shooed away for a second.
In addition, there was an overflowing septic system that was leaking onto the ground within about 25 feet of the three ladies preparing the tamales that was an awful smell that drew in the flies.
I never have, but after that, I sure would never eat food from one of the portable food trucks.