Pam -- That probably is true, that points can be earned on multiple purchases, however one cannot get the points without prior invitation (ie, having the link), this isn't a promotion that anyone can take advantage of.
Even as a MyPoints memeber, after contacting customer service asking to have the link for this offer, all I got was an answer to make sure that I indicated an interest in all product areas in my profile to ensure the maximum number of email offers.
I guess I'm not the left-handed, veggitarian, who prefers middle seats, with 20/20 vision who the marketing people targeted for this bonus offer....
(Not that there's anything wrong with left-handers, veggitarians, those who prefer middle seats or those with perfect vision.)