Why don’t certain celebrities have bodyguards?

I know the President of the United States is bodyguard all the time and even celebrities that are very famous like Bruce Willis, Johnny Depp, and all those famous stars have bodyguards. But why don’t athletes? I saw Ben Rothensburger in the Pittsburgh area and he was at the restaurant with his wife and people were bothering him like crazy and he wasn’t bodyguarded. Why is that? Athletes and tv reporters don’t have bodyguards it seems like.