I'm assuming because the mortality rate of Walleye in a livewell is much higher than that of Bass. Generally Walleyes are caught at greater depths so temperature shock is an issue. Walleyes also like to "nose" into the corners of the livewell making them susceptible to being beat up when traveling in rough water.
Besides...Walleye are tastier than Bass...no shortage of people willing to take the dead ones...lol
That being said there are live release Walleye tournaments...they are usually on a catch/photo/release basis...like the Rapala Quinte Gold Tournament.
Key off, yes you can. Most of the ATV batteries have 2 rates, something like 10 amps for 1 hour or 2 amps for 5-6 hours. I like the slow method. Don't overcharge AGM batteries, they don't like it.
Went up north into the woods. Had a net man/camera man this time. Armed with lures made by board member Misfish. One lure caught lakers, bass and white fish. Caught some real nice ones. Drove around in the boat about 80miles. Had great company so not much talking to myself. One night it was almost 0deg. I had to get up at 2 am and hook up a new propane tank. Almost froze it was so cold.