Game, set match.
Volt's can 'capably' tow a 4x8 trailer, loaded, cross country, through hills, while averaging 22-24mpg without any charging enroute:
https://www.reddit.com/r/volt/comments/6suzpe/towed_a_4x8_uhaul_across_the_us_ama/
Also found out a 6'4 man can sleep in the back...