Without wishing to 'brag' about the Invitation to Join E-Rewards, I actually have
two accounts!
I've had one for a few years (invited
via FB, IIRC) and I have steadily been accruing points (= around 1,000 miles per year

) ...
Then, a month or two ago, I received an email from HHonors with a special offer for 500 free points if I joined the e-rewards program - which I did!
So, as my two profiles are very similar (surprise, surprise), I get asked to do most of the surveys twice ... if I can be bothered, then I double my accrual rate.
-- Henry