Some business owners have to pay $50 for one person in one day of working as servant in the restaurants or coffee.

Restaurants, Coffee Shops Open Through Tet to Get First Profits
For many years until 2012 at least, there used to be the custom that all kind of restaurants or food courts closed completely during the Lunar New Year. Thus that is very difficult for people to find the place to eat or drink when they feel bored with Chung cakes or all kinds of Lunar New Year foods.
But in recent years, this custom has changed. There are many reasons for that. Firstly, many people have changed their lifestyles. They shorten the Lunar New Year holidays by holding less family parties and have time for themselves or their own families only. Before that, so much time and efforts have been spent for the extended families. 
For some families, especially in the urban areas, their Lunar New Year celebration ended on the third or even the second day after the first day of the New Year. Then families start to travel or going out to pray in the pagodas or temples. Then they go out for eating in the restaurants or coffee shops. 
Thus in about 3 recent years, there have been more and more restaurants and coffee shops opening to meet the demand of those people. But one thing for sure is customers must be ready to pay the high prices for the services they want.
During the Lunar New Year, most manual laborers will go back to their hometowns in other provinces, they never stay even if they can be paid very high salary. During those occasions, business owners have to mobilize the family members and relatives living in Hanoi to work for them, and for sure the fees they have to pay are not low. 
It is easy to understand why customers have to be ready for paying high prices for food and services during the Lunar New Year. From Bizlive investigation, some business owners have to pay $50 for one person in one day of working as servant in the restaurants or coffee. Thus all those costs will be passed onto the food prices or service fees to customers.
Even at such prices, many people are happy to pay. They would rather pay high prices rather than staying indoors telling the same stories to almost the same people Tet after Tet.