What is the benefit of the sacrifice bunt with a man on first?

My guess is that there afraid that the hitter would hit into the double play....and after a double play you've got 2 outs and no one on....with a good bunt at least there will only be out out and a runner on second...you rarely ever see a bunt turn into a double play and pretty much the worst case scenario would be they get the lead runner out at second....so I guess my opinion is it is basically to stay out of the double play...