What's the Point?

You often hear about couples having to get used to each others' differences after marriage. The one I always seem to hear about though, is the controversial toilet-paper roll positioning. Many like the end of the paper to come from the bottom, while others, such as myself, prefer the tp to roll off of the top. So, here's my question: Why do people argue about small and insignificant differences following marriage, rather than simply compromising?
I guess the first thing for myself would be the difficulty of making new habbits. It's not always easy to get used to new habbits or tendencies. When my parents got married, my dad would take his socks off and leave them lying on the floor when he got home. This drove my mom crazy, but it was simply a habbit. It's not an easy thing to overcome any sort of habitual trait.
The second reason for making small things into a large dramatic deal would probably be personal prefference and convenience. Even in my home now, I find it very annoying when the toilet paper is on with the end coming from the bottom. I don't make a very big deal of it, because most of my family feels the same way as I do. While I probably won't when I get married either, I will continue to put it on the way that I prefer, because it's a more convenient and economically beneficial way of putting the toilet paper on the roll. It doesn't take as long do find the darn end.
This brings me to the third reason for doing things how you want them done. STUBBORNESS! (I hope I spelt that right, or else I totally ruined the dramatic effect of all CAPS. Oh well.) At my house, we have a few stubborn people (myself) who like to be right. When we get into an argument, even if it's humorous, there are a couple of us who are determined to win. If you put two people like this into the toilet paper situation, that roll-holder will never have a roll put on the same way as the one before it. People like to have things the way that they want them. We, as a general society, want to get what we want. Man, we're spoiled.
Finally, the last reason that compromise isn't made in situations like this is our environment growing up. This one kind of ties back into each of the others. Our habits are often formed for us in our homes, where we develop our prefferences. When I get married, I'll want to make chicken soup and bread on Sundays, because that's what I do now. If my husband doesn't like that, that'll just be too bad. This kind of brings it all together. My habits of making soup, as well as my environment, prefference and, yes my stubborness, will keep me from compromising away from my homemade Sunday dinner. While some people are just OCD or controll freaks, these are probably the four main reasons that people avoid compromise after marriage or any new arrangements.