My barber in Italy just doesn't make me a receipt in exchange for a discount if I pay him cash so he doesn't have to pay taxes. Come on... the cost to operating a small business are usually low/there are tax exceptions, and they most of the time are even not payed at all.

Of course if you are a person that ships 20 packages you don't register a company to do so, nobody will, you just sell them privately (and the exception to sell things privately is quite high, in my country you can do it up to 5000 euros AT YEAR, after that you need to declare the income in your tax declaration but still you don't need to register a company if it's not your main income).