I have been visiting SF auto show and San Jose auto show on and off for the last 15 years.
Though I have A100, A77II, A900 and A99M2 and had A700 (which is now in the hands of a committed photographer)
I did not feel the need for 2 bodies. I was always able to swap lenses with relative ease.
My typical soirees include air shows, car shows, car races and of course travel. Though there were times I wish I had two
bodies it was not very often. One time at San Jose car show I had a 70-300 Sigma and regretted it. Auto shows tend to be crowded
and very seldom I needed more than a 24-70 rarely get a chance to use 70mm. My Flickr account does not do justice because till couple of months ago I had a low speed internet and uploading was a pain. Car races needed both WA and zooms but never at the same time. Same is true with air shows where there are static displays and airshows. For travel, my big concern was that two bodies would attract attention of thieves. I would put on a big zoom only where I feel it is "relatively" safe. For example during my Brazil visit, it was A77M2 with 16-80 most of the time. Only time the 70-400 came out was on Amazon river boat cruise and at Igauzu falls.
I have used Megapixels as a substitute for zoom where I felt the need but did not have a 2nd body. To wit the following was taken inside the Duomo in Florence, Italy and the second shot is a crop. The 24MP of A900 to the rescue.
Crop 12o Clock from the center.
Another example where I could have used two bodies but took advantage of pixels and a single body.
A99M2 with 24-70
Why would I need two cameras?