The "Saturday is a waste" idea seems to be a self-fulfilling catch 22 prophecy these days.
Some sellers say to themselves "no one here buying so I'm packing up early" (ignoring that people can't be everywhere at one time, and it takes time to see the halls, as Gerhardt mentions above). Some sellers tend to evaluate based on foot traffic over an hour's time, and decide to give up and start packing it up (or even totally bail) in the early hours.
Buyers then say "Why do I want to bother going on Saturday, with everyone packing up or gone?".
Repeat. And it all comes true that way and Saturday continues to be a waste. This drove me nuts too when I was a buyer. Sellers say "well you should have come earlier". Well, I was there earlier, but you can't see the whole Fairgrounds in one hour to peruse every table in the first 1 1/2 hours of the meet.
HOPEFULLY, the change means people give Saturday another chance. It might actually be busier without Thursday leading off. But it won't be if everyone has already decided that Saturday will still be a waste before even giving it a chance.
There were probably people who didn't stay for Saturday back when it used to be just Friday and Saturday, but I suspect there were a lot more who stuck around than there are now. I don't think it will ever return to the levels of those days, but hopefully this makes Saturday better.
As for me, with my small table setup, I sold 4 pieces (marketed and sold as 2 pairs actually, so really 2 sales - though I had single pricing available as well) of rolling stock on Saturday that I wanted gone. My other sales were all on Friday, I sold absolutely nothing on Thursday. $$-wise, probably about 35% of my take home was those Saturday sales. So I'm glad I was there, and the people who bought my items seemed happy with the prices they paid.
I did have a buyer who I had sold a few small items in the past wander past my table in the last half hour or so. While I had started packing a little bit, I still had everything not yet sold on the table (I had put stuff back in shipping cartons though). So I told him what was in all the boxes (recognizing him, but not remembering if it was from earlier this meet or previous ones when we had interacted). He only had a chance to attend on Saturday.
As a seller who still likes to participate in the buying side of the transaction as well, my bigger concern is the lack of time after Member halls close to go browse the Dealer halls.
In the 3 day format, we had 1 1/2 hours on both Thursday and Friday (5PM - 6:30 PM). (and there is a chance it used to actually be 2 hours, didn't the Dealer halls used to close at 7 pm years ago? (I need to find an old meet flyer)).
The new hours I am pretty sure end at 6 PM for Dealer halls on Friday, and on Saturday I don't think there is any time at all. I believe both Member and Dealer halls close at the exact same time. This is not good, IMO. I'm not sure it's worth having a table when I have only one hour to browse on Friday after the Member halls close. I'm pretty sure I'll still do it for April, but after that is to be determined.
-Dave