I have always thought it was a move by the airlines and soda vendors to sell more drinks on planes, by preventing people from bringing a bottle of juice or water with them.

You can bring as much water as you like on a plane, as long as you buy it in the secure area after the security check. (And it doesn't take up your neighbour's seat in the air.)

So yes - very possibly. But I'd wonder if there was a trade-off between extra soda sales and lower flight numbers. Some people still aren't happy about the ban, and it's a huge inconvenience for anyone travelling with a baby.

they haven't banned vegetables on planes yet.

Especially not on Air Force One.

(Or in the Oval Office.)