The procedure described is mandated by the Society. Like you said, it is distressingly ritualistic. To what extent each congregation follows the ritual might depend on the COBOE or brother giving the talk. I used to give the talk every other year and this ritual passing used to bother me very much. It wasn't enough that the speaker gave the emblems to each attendant. He had to sit down afterwards and be handed them by one of the attendants.
Rant starts here: Its not enough to just come and "observe" like the Society says. Its as if the Society is adamant that you accept their superiority by your physically refusing the emblems (knowing that they do partake). It is also dishonest to the outsiders who accept the invite to attend. They are invited to observe and then find themselves having to make a choice. Imagine going to some other function 'just to see what is going on,' and then finding yourself being somewhat forced to participate. I could see how this might bother someone who thought partaking was the norm and then finding themselves having to decide what to do with everyone else turning down the emblems and the speaker encouraging the same.
I figured out a few years ago that all Christians were to partake. I was intending to go to a different congregation but the other elders volunteered me to give the talk. I could 'feel' every eye on me as I was the last to be handed the emblems. I told the brother who was going to hand them to me just before the meeting so he wouldn't have a stroke.
The real shame of it all is the Society's 'published' view that many who partake are 'mentally unstable' or 'influenced by past beliefs.' But they won't say the real reason the number is going up. People are figuring out that they are lying about who should partake. And its a shame also that if you came out and said you partook because all Christians should, you would be put out for apostasy. I seem to remember 'Narkissos' saying something about this very thing. I wish I could talk to him about it.
Here is another way you can see that the WT doesn't see things correctly: In the Bible, the reason for partaking is to 'remember Jesus,' to 'keep proclaiming the death of the Lord.' In the Kingdom Hall if you partake, the immediate and only response is: 'So you think you are going to heaven.'