I find this obsession with drinking and driving hilarious. Normal humans dont drink litre/gallon cups of coffee, we get a normal human sized coffee which will easily fit in the cupholder and we drink it while it’s hot over a 5-10 minute period. Normal humans also stop every 2 hours for a break or to change drivers, during which time if you really must drink litres/gallons of water a day you can refill or change your water receptacle, and if you do drink that much you will definitely need to stop regularly for a pee. Of all of the things I would like different or to change or modify about the Grenadier cup holders are the very last on the list. If I still had kids that traveled with me, I might make an exception for rear cupholders, but just normal human sized ones not litre/gallon sized ones.
Rant over.