Something that hasn't been addressed here is this.
If the Bride had the time to assemble the papers, pens and lists of the gifts that should be acknowledged, if she had the time to provide the names and addresses of those who should receive TYs to her Bridesmaids, she had the time to write the ding-dangety things herself.
I did help out with TYs when FIL died. MIL wrote the notes. I addressed them, put the postage on the envelopes and mailed them. To me, this was a reasonable way to handle the situation.
What the OP relates is not reasonable at all. Bridal attendants came for a lovely meal and found a box at their places. They think it may be a gift. Instead, it becomes something out of a Dickensean novel.
'When you have finished writing your 70 TYs to my satisfaction, you may begin to think about ordering something to eat'.
Given the story, I wouldn't be surprised if the Bride didn't strongly suggest burgers and fries all
around. While she enjoyed filet mignon.