Also, much of the Marx Bros. humor was topical and relevant to the climate of the time (twenties and thirties). Therefore, if you are not up on what was going on at that time, a lot of the jokes will go right over your head. References to celebrities and events of those years will not mean a thing to the average 20 year old of 2008.
Such as Groucho Marx engaging in his Eugene O’Neill interludes in “Animal Crackers”.