There is no need to set up a .printers file in your users' home directories if they don't need customized printer information. However, the .printers file enables users to establish their own custom printer aliases. You can use the alias _default to make a printer the default and also set up a special alias _all to define a list of printers affected when you cancel a print request or check the status of printers.
Keep in mind that the LP commands check a user's home directory to locate printer configuration information before they check the name service. This means you can tailor a user's printer configuration file to use custom printer information rather than the shared information in the name service.
See printers(4) for detailed information about the .printers file.