DW got it for DD, but to me a more important consideration is whether there is any actual benefit to membership. And I think the answer to that is "No."
If college admissions placed any value on membership, there there would be some benefit. But I don't think they do. Most colleges look at GPA, weighted GPA, class rank, SAT/ACT scores, and/or extra-curriculars. I don't think a certificate you paid $75 for would have much weight for college admissions.
I think they do give a cord for the graduate to wear on graduation day, but some high schools do not recognize the organization and will not permit wearing their cord.