I've dry fired Smith revolvers untold numbers of times over the past 30 years, and never ever had a problem with them.
I don't dry fire my Rugers as much any more, after breaking transfer bars in two different guns. I'm going to get snap caps and use them. As was mentioned, it is cheap insurance.
My transfer bars broke at home while dry firing, it could have happened just as easily on the first shot when a bear was closing in. If all you have your gun for is trips to the range, then I say have at it and dry fire them full time without snap caps. If you think you may want to have it work on some dark night when things go bad, then cheap insurance takes on a new meaning.