Guy at the gym uses collars, and uses DL straps when he's benching. (Wrenches his fucking hands to the bar).
Literally tying himself to a barbell that he struggles with.
The only good reason I see for using wrist straps for bench press is to somehow secure the hand to the bar when using a thumbless grip.
I did it in the past, it's actually not bad at all.
The other reason I could see is to relieve forearm pain around the extensors area

I remember helping a buddy of mine with this little trick. He was complaining about forearm/hand pain when benchin. I threw my pair of straps at him and said, "try it with these."
He was desperate so he did, and lo and behold, he didn't feel any pain during the set