The straps that are shaped like a loop are olympic lifting straps.....they are designed that way so that you can release them to properly catch your cleans and snatches......you cannot use them in competition, but a lot of lifters train with them at times.
Personally, I will overload my pulling muscles and use straps on my clean and snatch pulls and my shrugs and rows.....I never use straps on the actual lifts themselves.....I never use them for deadlifts either. I always felt straps are a good way to overload the upper back muscles because they are so large and just require it at times, however, they are not an excuse to have a weak grip.