Apparently when the two Atari 8-bit machines were released, the 400 outsold the 800 2 to 1, which is unsurprising considering they were priced at approximately $500 and $1000 respectively.
Indeed, the surprise is that the ratio was not higher. Granted the 800 had an extra cartridge slot; that doesn't jump out as being a very important feature; it at least looks like one in three customers were willing to pay an extra $500 largely or entirely for a better keyboard. Which would be very logical for a productivity machine, but more surprising for a machine whose primary selling point was games.
Were those one in three customers really paying for the better keyboard, or did the 800 have some other selling point I'm not taking into account?