BS or not regarding battery?

Battery died overnight. No lights were left on in the car, nothing unusual in terms of weather. Car is used three times a week For about 25 minutes each time, it's our son's car and we drive it Multiple times a week while he's away at school. '19 Continental reserve, ttv6 if that matters. I Take the battery in to claim the warranty after testing it, 7-year prorated warranty, battery is 6 months old. Manager of the shop says he won't replace the battery a second time if it dies. He's claiming unless we're using the car every day for *40 minutes at a time*, the battery is going to die and this is what's going to happen. And I'm thinking to myself 1. A lot of people work from home and probably don't even drive three times a week, and 2. most people don't drive 40 minutes every time they're in the car (I understand that taking a bunch of 3 minute trips isn't good, but that's not what we're doing with the car). So I asked him how far he lives from the shop, he says 15 minutes. I ask him if his battery dies every 6 months? He doesn't actually have an answer and Rings up the exchange. Was I out of place to challenge him on what I thought was an absurd claim that you need to drive a car *every day for 40 minutes* to properly charge the battery? Wasn't trying to be a jackass but this was their top end battery and I bought it for that reason. And the OE battery lasted 5 yrs.