Marcus, I have been reloading for decades and I've never annealed yet.  I would venture to say that with careful reloading and relatively low pressures, your brass should last a very long time. 

That said, I am going to anneal all of my brass this weekend!  If I had known about this, I would have been annealing my brass all along...  An inexpensive butane or propane torch should be available at your local walmart.  I see it as a simple yet effective trick to preserve brass for decades to come.  Even if you don't plan to shoot much in the future, there may come a time when you will... and good brass might not be readily available.

I am truly grateful to Butlersrangers, Parashooter and kirk, and all of the other posters who have helped me to learn way more than I ever could have learned on my own!