I can't speak for others, but I've used computer w&b programs to explore loading configurations, and experiment with different loads to see what will happen when I move something from here to there. It's easy on a computer, and lets me learn where and when I need to be careful with an actual calculation. I have both Palm and PC programs, and while I seldom, if ever, use them for actual calculations, they can show worst-case scenarios, and whether I'm likely to have a problem. Having programs for aircraft that I don't even fly is also instructive. When it comes to calculating the actual weight and balance of the aircraft I'm about to pull pitch in, I use the approved method of calculation, but it's educational to play with other calculations while I'm not flying.