No business will survive for long on day tripper custom alone. Day trippers will not be attracted to a place if its obvious that its not prospering from local custom, even in honeypots like Temple Bar.
To be frank, anyone would need to be drunk, stoned or out of their mind to eat out of any of those places, and I don't see why public monies should be spent on protecting the blue plastic bag brigade from their own stupidity and excess.
It doesn't matter how long the business operates or has operated for - the main focus has to be on the experience of the person eating there. When you're abroad you are often eating at off-peak times, so it is difficult to tell when a place is just having a quiet period or if its permanently empty. Likewise most reputable, good restaurants also have quiet periods, especially during this recession. Someone on a day trip or a tourist won't have the capacity for comparision always.
As regards the hotdog stand. Sometimes people don't have a choice in eating at sports events etc as choice is limited. If someone has a business supplying food then they should follow health regulations. Consumers need to trust that suppliers are doing things properly, especially regards food. Some people don't have the choice to pass by - i remember being at a match when my dad's glucose (he has diabetes) went low, and we had to buy food from a stand as an emergency measure. it doesn't make him an idiot for having to buy there, he had no choice and he has the right to expect the food is up to standard. If someone has a business, their products and services should be up to standard, especially as regards health.
If that hot dog guy wasn't storing his food right, im glad he was caught. Next time he might be more careful and someone might avoid getting sick, and having to paying doctors fee and missing days off work etc.
I genuinely don't understand your argument. You seem to be saying that gradual gossip can close down places naturally, and thus save paying inspectors.
Standards can be shonky enough in restaurants as is, and i can't even imagine how lax it would get if there were no checks at all. Also waiting for enough people to get sick so that a restaurant gets a reputation just seems to be downright dangerous. Food poisioning can be lethal for young children, the elderly, or people with cancer or low immune systems.