Not everything in a country can run by a government so which itself enough why we need private sectors to keep things in balance, of course government bend their rules in favour of them for whatever reasons while private sectors create job opportunities that again help someone to make money and they will spend the money they earned so that will obviously help in the development of economy in a country.
A country where the government handles everything will definitely not be called capitalism. In a capitalist country, the private sectors are the drivers of the economy, they create more jobs and help in engineering the circulation of funds. What the government do mainly is to create the enabling environment for the private sector to thrive. As soon as the enabling environment are created through programs and policies, the private sector will naturally spring up and flourish and this is how a responsible government is measured. Monetary policies, ease of doing business, basic and social amenities are some of the things that constitute the enabling environment and these are the core responsibilities of the government.