I think the US is more paranoid about flu. Perhaps wanting to avoid getting it, or to avoid the multiday "death warmed over" feeling. I guess if you get it once (and feel that bad from it) you want to tkae precautions.

I personally do not get flu shots. I asked my doctor about it a few years back, and his recommendation was to only get it if you are: in a high risk group (very young or old or with existing medical problems), caring full time for someone at high risk or exposed to lots of high risk people at work (medical, education, etc.). So, I have not gotten any flu shots and I personally do not recommend it for those reasons.