Every year the post office hires people to sell New Year's cards.
The post office recruits people every year to sell New Year's cards.
“dispense” は「配る」意味ですから、年賀状の販売とは少し違います。
他に “dispense” を使う例文:
“The soap dispenser is empty.” (石鹸のディスペンサーが空っぽです。)
“The army is dispensing food to the disaster victims.” (軍が震災の被害者に食料を配っています。)
やめる意味もあります。例えば:
“Dispense with the pleasantries and tell me what you want already!” (遠回りの話をせず、はやく用件を言いなさい!)