That's exactly right. Rattlers are not agressive, and you darn near have to step on one or pick one up to get him to bite you. I think there are VERY few exceptions to this, surprising one while being very close to it being one. I've come within 2 feet of 2 rattlesnakes, and neither knew I was there. The first one, I didn't know until I looked down, and I did the world record for the standing broad jump.
Of course, both were shot, as I shoot any poisonous snake that's not hightailing it away from me. I never venture off the beaten path in Texas without a sidearm at minimum and a sawed off shotgun usually.
I've had three close calls (within a foot)with rattlers this sumer alone, and did a few quick maneuvers myself, but why would you shoot them? I usually just stand on the trail watching them until they are off into the brush, just to make sure they are well gone before the next hiker comes along.