I strongly suspect that I am not alone in the stubbornness of my toothpaste preference. I will grudgingly use a different shampoo if I have to as most shampoos don't have too strong of a smell. In any given day I use probably 3 to 6 different soaps, with only the one in my house being my preference (mmmmmmmm coconut ginger) so using some random soap at a hotel is no big deal. But I will be buried deep in the ground before I subject myself to using anything but my usual toothpaste.
It took me years to find a flavor of mint that I honestly enjoy using. Nothing else has ever felt quite right; it even has the right texture! Using another flavor for even one brushing would make me want to gag. Taste, in both senses of the word, is a very personal thing I suppose.