Over time and with use, strings do corrode and it does affect the sound - not just the tone. I'm pretty sure that time over tension would also reduce the integrity of the material. It may also affect intonation. Of course, bass strings last longer than guitar strings because of the gauge, but they should be replaced if you are going to do some professional recording or performing.
I don't see it as changing tires. I see it as changing underwear. Sure, it's convenient to just keep wearing the same pair, but other people probably won't appreciate it as much as you do.