What is 'Toofer'?
Stephen King wrote as below:
I had given up the ghost in 1978 to make way for a video-games arcade called Galaxia and E-Z Video Rentals, where Tuesday was Toofers Day and no one under the age of twenty could go in the back room.

What is 'Toofer' here? Does it mean 24 packs of beer?

Question

What is 'Toofer'?
Stephen King wrote as below:
I had given up the ghost in 1978 to make way for a video-games arcade called Galaxia and E-Z Video Rentals, where Tuesday was Toofers Day and no one under the age of twenty could go in the back room.

What is 'Toofer' here? Does it mean 24 packs of beer?

Answer

A "Toofer" or "Twofer" is when you get two of something for the price of one thing.  Here, he is talking about a video rental store which means that you got two video rentals for the price of one on Tuesdays.  The "back room" would be where the adult movies (porn) were kept which would explain why nobody under 20 was allowed in there.

Answer

What I always remembered was "two-fers" which was two drinks when you ordered one.
In this context it might refer to 2 x10 or people of age 20 or older.

Answer

I think you mean "twofer". Twofer means two for the price of one. In this case, he probably meant you could buy two drinks for the price of one drink.