I believe it is always prudent to carry certain items in a car just in case.
Although cars are inherently more reliable nowadays there is the 'oh my what just happened' scenario and even if you are caught short, it is then you are most grateful for the little things (like water, toilet roll, first aid kit).
Apart from the bottled water I always have in my cars, I have never needed the other items I carry around but if I took them out then according to the Law of Sod then this is when I will need them most 😞