Well this is an interesting topic. A large proportion of Lao people who live on less than $1 a day are those who live in the countryside so money is not usually a problem because they don't have alot of expenditure.
The great advantage of living in countryside of Laos is that land is cheap to own. Most people work as farmers and they grow their own rice and vegetables for their own consumption and also for sale. They don't often buy food.
Also, most households in the countryside have animals such as chickens and ducks and these are raised for sale in the markets or bought by other villages. During their spare time rural Laotians make and sell handicrafts at home for extra income, so as you can see there is always money to be made somewhere.
In the city, most workers earn more than $3 a day on average. Monthly expenditure is higher because city people enjoy shopping, entertainment, buy food, petrol, plus the high usage of electricity and water. Bills are usually shared within the family and that's how they get by.
Compared to most countries, the cost of living in Laos is generally low because Laos is an undeveloped country and people don't earn alot of money from their jobs, therefore the cost of goods and services needs to be within the bounds of what people can afford.
In Laos, tax is low, food prices are low, utility bills are low and people own their homes without paying mortgage loans. Lao people can survive, but the flip side is that they don't usually have any money to save on a small income. Sometimes people who are lucky to have relatives from overseas send them some money when they are in need.