It really is a matter of, "to each his own."
For those who are anti-device, what is your opinion on directional poles? How about a yardage plate on a par 3? Would you look at it to aid in club selection? How about a putt that is on a similar line to your own? Would you watch it before playing your own ball?
It's an interesting debate, because, unlike almost every other sport, there is a lot of downtime in golf to think about and analyze what is going on. I think many golfers get information overload and can become paralyzed before playing a shot. In almost every other sport, athletes don't want to think, they want to react. They want to be fluid and do what comes naturally, to be free flowing and let their body do what they've trained it to do.
I always play best when I think less and just hit shots. As stated earlier, I do use a device to provide front, middle and back distances. I find this helps me play quicker.
In the end, guys should do what makes the game of golf most fun for them, because, really, that's what golf is all about; fun.