I don't think you can be too hard on someone that takes a couple of shots . . . you have to remember that he was probably surprised by the snake and probably a little "shook up" as well.
Five years ago we started to winter in Arizona - we only have one type of rattler in Michigan and in my 60 years, I've only seen two and they were pictures in the local paper where someone had 'em show up in their yard. I live around swamps and on a farm and we never saw 'em there.
Now, transplant me to AZ and the first few I saw scared the snot out of me. I suppose when you grow up with 'em, you're used to 'em. We have even run our dogs through "rattlesnake aversion training" and while we have a house in a developed community in AZ, they are around. I just try to keep alert - not only for myself but the dogs as well. I don't know which I hate more - the rattlers or the Javelenas that come into our yard and eat our plants.
We had a smaller rattler come up in our drive by the house one time and I quickly dispatched it with a shovel. When we mentioned it to one of the neighbors (who is a tree hugger type) she got all bent out of shape because I smacked it. I tried to explain that I really didn't kill it - it just was in such a hurry trying to get away that it smacked its head on my shovel and committed suicide. We an call our local FD if we spot one and they will come and pick it up and transplant it back int he desert. In talking with one of the firemen, they usually average about 3,000 snakes a year - a lot more than I expected.
If a pair of '51 Navies were good enough for Billy Hickok, then a single Navy on my right hip is good enough for me . . . besides . . . I'm probably only half as good as he was anyways. Hiram's Rangers Badge #63