That's typical. Simply put alcohol will bear a higher markup in any given market than food would. Simply put people are willing to pay more for alcohol so we can include a higher markup. And the whole trick with breaking even in a restaurant is that you use high margin items to cover lower margin items. What's important is not that every item has a given profit margin, but that the whole of the products you are selling average to a workable margin.
So for example my place has a hefty pizza take out business. I forget the exact numbers on what the pizza costs all in to make, throw in a box and send out the door. But people won't pay too much even for good pizza (and ours is very good). We sell at around $18 bucks a pie, and they cost us more than 8 dollars to make. In the end profit off a given pizza is in the $2 range. Standard domestic beer costs us $.85 a bottle. We sell it for 5 dollars. There's less time, staff, and logistics involved so the beer generates more profit out of its $5. Profit there is around $3. We make more off a shit beer than we make off the excellent pizza that brings people in the door. But that higher margin off the beer allows us to keep the price of the pizza below $20 dollars.
It is not. Not in the US, and I'd be willing to bet not world wide. People do get rich running restaurants. But that is relatively rare. You need very high volume of sales. The right location. And the right economy. Some one is working their ass off even in the bad failing restaurants. For the most part a successful restaurant will make a decent middle class to upper middle class income for a working owner. Or for a staffer or two (usually Chef and Manager). Doing better than that is a function of location, size, chance, and frequently owning your own building. And I've seen plenty of restaurants that have made their owners fist fulls of money that are absolute crap, and where the owner is an absentee investor. In fact some of the most successful guys in the business are casual chain restaurant franchisees. The kind of guy who owns the local Applebees.
People think restaurants make tons of money hand over fist. Because we mostly see and hear about those who have been very successful.
It is much more possible to make great money running a Bar, especially one that does not serve any food, because the overhead is much lower. There is less expense, less waste, less equipment, less staff, and you cut off the major margin sink that is food production. Average profits in pure bars are closer to 20%+ than the 10% average of restaurants as a whole.
But the major way to actuall have a profitable restaurant or bar business is to own more than one. The rule of thumb is this business is that a restaurant does not make money. Restaurants make money. With more than one location, and owning at least some of the properties. You get several things. You can take advantage of economies of scale unified ordering for the whole group allows you to bring wholesale costs on everything down. Food, liquor, equipment. Leading to higher profit margins. Multiple locations allow you to cover more bases in the market. Multiple pure bars generate much higher profits so they can offset lower margin casual dining locations. Which can subsidize and stabilize and profitable but unstable high end fine dining spot. Spreading advertising and marketing costs, insurance and payroll costs over multiple businesses makes them less of a burden on each individual location. And so forth.
This is why you see the huge spike is "fast casual" high end spots in the US. Like Shake Shack and the like. Those places have much lower overhead, and higher profit margins. So as the lynch pin of a restaurant group (together with bars) they can fund all sorts of wacky shit that wouldn't be long lived on its own.