I work in a job where clean unshredded hands are vital. Also i don't want sore, callussed, cut to ribbons hands when I am playing with the kids or cosying up to mrs gd! And that is before the chopping of fierce chilli or use of feisty spices in the kitchen. A bit of abrasion protection is well worth it.
I have ridden in gloves for so long I cant tell you if they have any.grip advantage but if they are not on on.the mtb it feels wierd.