Emily Post 1950

 Emily Post Says:

 Greeting Cards Need No Reply

 Emily Post, the etiquette authority on, well,
most EVERYTHING, had advice for greeting cards, too!  
This 1950 newspaper article indicates a change in previous etiquette

"Dear Mrs. Post: 
Lately some of our friends have ignored birthday greetings we've sent them.  Their reason is that it is no longer necessary to acknowledge cards of any kind.
I personally would think that lack of acknowledgement makes such greetings seem unimportant.  What is your opinion?

Answer:  The only acknowledgement that is expected of a greeting card is to send return cards at suitable times.  To have to write a thank you for every greeting card would dampen the joy of receiving many!"

 source: The Miami News December 28, 1950
http://www.etsy.com/shop/vintagerecycling