Almost no-one will make a 50 km trip with a cargo bike. But it's quite likely they don't own a costly and space-hogging car, but will rent one for the few times they need one.
(Note: 50 km is the equivalent of the 30 miles in parent's original comment.)
I do trips in that range for weekends and holidays. Kid loves sitting up front and 70-90km is definitely an achievable distance - about 5 hours of riding time.
(Note: 50 km is the equivalent of the 30 miles in parent's original comment.)