Pilg, What you were seeing was clearly on display again during the past half hour. Agreed, no apparent sense at first glance. I was first mystified by this back in 2008 during the Gold Eagle run up, and only this year figured out what was going on.

"The point" is price suppression using high frequency trading with algos. (It can be applied to work in the other direction too.) Read the book Dark Pools.

The regulators sanction this with neglect because the exchanges want the trade volumes created by HFT. We have the tail wagging the dog.