Totally. I have been to many parties where a guy would whip it out but usually he was drunk and limp. We did have a guy friend though who was reputed to have a huge dick, all of his friends would joke about it. We were at a hotel while on spring vacation (6 of us) and my gf and I were laying on a bed and the subject came up. I said "OK look B--- come over here and show me" and I put my hand out. He just walked over and flopped his dick in my hand. Of course we all laughed hysterically and it was indeed VERY big.
Another time we were over at a friends house and a guy came over. The guys all said he had a huge dick and we said "yeah right, whatever". So this guy whips out his dick and it was seriously one of the biggest dicks I've ever seen. (He was black if that makes any difference) I would honestly guess it was at least 8.5-9". He kinda looked like he'd gotten that reaction a LOT, so to him it was no biggie to just pull it out and show girls.