I live when we are emailed "anonymous" surveys with a query string. It's even better when they are engineering specific surveys because at that point you have to question if they even think you can do the job if they thought they could get blatant tracking like that past any engineer
I saw such everytime too. These tracking params are to guarantee that the survey is filled only once by a person. But tracking is possible if email and the survey match is stored somewhere. It is all up to trust.
