Buy Marriott vacation points through Marriott or Redweek?

We attended a Marriott VC presentation today and were offered a package of 2,000 points for $23,000. Can someone explain why purchasing 2,000 points through Redweek is drastically less expensive than purchasing directly through Marriott? What would we be missing out on if we purchase through Redweek?

I also very recently attended a MVC sales presentation, and now trying to compare against resale too, would love to compare notes with you and others. This is what I got thus far:

Direct: 1. You get "some" bonus point, I think in your case of 2000 points, you get 4000 1-time non-recurring bonus points 2. The transaction is less risky, because we are buying from Marriott directly, as opposed to buying through a marketplace (e.g. Redweek) which probably doesn't want any liability if the seller turns out to be a fraud, so we better know what we are doing 3. You become a Marriott Bonvoy Platinum member (I am not sure if you get the same thing at resale)

Resale: 1. Way cheaper (BUT keep in mind Marriott has ROFR and even if the transaction goes through, the buyer will need to pay Marriott a mandatory $2/point "transaction fee" + $30 "education fee", so you need to factor that into the total cost 2. Some postings may offer banked points to make it more comparable to the direct "bonus" points, but these are usually hard to find

We all have our own feelings towards timeshare, but hopefully I was unbiased enough to only provide facts above. Look forward to see other people's comparisons.