Hey that is a very interesting question. If i were to buy a male friend a wedding gift, i will ask myself these 2 questions first:
1) Is he into grooming?
2) Are you just buying for your male friend or for the wedded couple.
If answer is yes for (1), i might buy a nice facial and treatment package for my male friend prior to the wedding and to give it to him early. As his big day approach, it will be great for him to go for facial so that he can look his best during the big day.
For (2), if you are buying for the wedded couple, you can give very practical things like a love gift (money), so they can buy something they would like or to pay off the huge bill they will have from the wedding. Or if you are open, you can even get a nice bottle of wine, for both of them to enjoy their first couple moments together.