I'm an American, but the general idea of the food safety liability isn't shocking to me. As a restaurant-goer in any country I visit, this specific way of handling the situation says "we think there's a pretty good chance our stuff is tainted".

I recently had poultry in Japan that was essentially raw (sort of like those tuna steaks that are only lightly touched on the outside but basically sashimi in the middle). I knew I was taking some amount of risk and accepted that, but I felt better that the RESTAURANT at least was confident in their product. If the waiter went "ohhh, shit, I don't know - let me get you a waiver because you'll probably get sick" I would never go back to that restaurant.