Precisely my point regarding Hansshow Power Frunk: Even in the event of a loss of 12V, all by my lonesome, I have immediate access to my emergency equipment. In addition to the Li-ion jumpstarter, I store a 1st aid kit, a tire repair kit&inflator, lug wrench, jack&pucks, paper towels, nitrile gloves, mobile charging cable with all the 240V adapters and a bottle of Invisible Glass in a ziplock bag. No sense in standing around waiting for someone else to respond, right?
As to your guess that aftermarket mods will void your warranty, if that happened due to a Power Frunk, I would speak with the SC Manager and cite Elon's own words to Sandy Monroe that their 'use of a 12V lead-acid battery is an inherent defect in their cars.' If that doesn't work, then I'd cite the Federal Magnuson-Moss Warranty Law. I suspect you'll get your free battery.