Elizabethan times were not Victorian times. There are certain things in 'Hamlet' which were included to amuse the vulgar crowd. One would not call these things "polite" by Victorian drawing room standards.
The correct actions have been lost over the years, partly just because of the passage of time, and partly as 'Hamlet' has become the province of theatrically-naive theoreticians, and as a result, has been interpreted more and more in an "academically correct" way.
However, correct actions can mostly be recovered from Shakespeare's dialogue. This is one case.