It's a custom from the European Jewry called a Tish. The men all sit around a table, the fathers sign a document for their children to be wed, the mothers of the children break a plate together (tradition...), then the men all have some hard liquor and sing for a bit. It's a joyous occasion. It's not alcoholism to have a some alcohol now and again. I can't believe you would equate alocholism with perhaps getting a little bit drunk, probably not even that.
By the way, I find it surprising that the women had anything to drink. Also, it's not a religious service, it's a wedding, a joyous celebration joining to people. There are religious aspects of it, but for the most part it's a celebration.
Also, no, I don't "get it." Just because the women are not liberal and have different traditions and customs than you have does not answer the question of why some people hate Jews. By the way, I'm conservative, I don't particularly like the "women's role" that the Orthodox Jews maintain, but it's not my place to say I hate them for it or criticize them for it just because I don't agree with it.