I've never felt the 'need' either.
I do it for fun - mostly when fishing grease liners for summer runs. It's cool feeling them take that loop from you. And it seems that every take is a little different.
I had a take last fall that seemed like it lasted for ten minutes, (I know it was just a few seconds though). The fly had swung well in to the slack water near shore when I noticed that something felt different with the line between my finger and thumb. With my other hand I gently, and slowly pulled in a few inches of line...just as gently, and just as slowly, a few inches of line were taken back out!
Grinning, I slyly pulled a couple more inches back in...now I could kinda feel him...so I slowly pulled in even more with the fish coming right along with it. It wasn't long before I had doubled the size of my holding loop. Well the last thing I wanted was more line lying on the water when this guy decided to do his torpedoe imitation so I waited...and waited...finally he ambled away and the loop began to shrink. Once the loop was gone I lifted the rod and things returned to normal - fish on!
Another time I had just sent out the cast and looked down to check the size of my loop. Just as I did, it vanished in a blink, the rod tip went under, and the reel started singing.
I don't know if a loop is good or bad - but damn is it fun!