If anyone has ever worked in a commercial kitchen they already know this.
There are bugs in restaurants. Period. It's that simple.
Even the the cleanest restaurants have bugs. Why? Because they are brought in with the food delivery in the never ending cases of food stuff bought.
And Even if the restaurant buys fresh ingredients there still will be cases of condiments and such. Roaches live in cases. They can eat for a year off of the glue used to put a single box together.
The real trick is how well the restaurant staff works to control them and to keep them contained to the store rooms only. When you find them in your food or drinks then they are in the kitchen and the staff is loosing the battle of containing and controlling them. When you see them in the dining room the battle is lost and they should be shutting down and getting professional help in extermination followed by a deep deep cleaning through out.
But if you think your favorite dive doesn't have bugs because you haven't seen any, you're wrong. And no owner is going to admit it. And even if they say they don't and beleave it, then they damn sure DO have em they just don't know it yet. They came in on this morning delivery.
How do I know. I have worked in the industry off and on for years. Since I was 14 or so. I've worked in mom and pop pizza restaurants, hotel chain restaurants and over the top '3 star' restaurants.
I've opened brand new restuarants that had just finished being built. Not a single bug in the place, six months after opening we saw our first one in the store room crawling out of a box. We fought them from that day on.
And the worst of them all are the fast food chains and corporate restaurants, the 'owners' are rarely there and the managers are there for the pay check. That's as far any anyone else's interest goes too.
If you don't want bugs near your food then stay home. Or just don't think about it.
Tyu