When I was still living in London, I used to go to occasional track days. I too thought like you. My cab was in perfect shape before each track day. After the day though, I had leaks here and then, clutch was starting to slip, brakes were half consumed and of course I started adding thing to my list that were needed. Better brakes, one more stress bar, stiffer rear springs etc etc.
So, if you can keep it just for fun and not become competitive with the rest of the boys, you'll be fine.