Personal preference I guess, some people like to have the latest gadgets and some like to have everything electric. I guess if your dragging a large 12V battery along you might as well use it.

For me I've found that I rarely do much useful changes or tinkering a the field, and now prefer to bring as little stuff as possible. Spare props and glow plugs etc. Hand fueling with suringe and handflipping engine etc. no batteries needed apart from a handheld glow driver, and not even that for the diesels.