Pay cash in hand is immoral

The government is claiming that they are losing stg 2 billion a year by people paying cash in hand and it's damaging the economy!
Which kind of school do these people go to?
1. By a plumber not paying tax he gets to keep more, which is the aim. Then he can spend it on his family or staying alive with food.
2. Lets the government make their figures transparent. A loss of Stg 2 billion by 2 million people as they suggest makes each one of them saving Stg 100,000 each! If they are not suggesting the man on the street then let them investigate medium to large company books! They are only whinging 'cos it stops their expense accounts going overboard! Is the government that strupid?yes of course they are, history proves it!!!