Recently, I cama across an article in a Jewish newspaper that showed 8 chuppahs in a row where 8 couples were married simultaneously. The reception, too, was for all 8 couples who were Russian Jews. Is there any problem of ‘ayn m’arvin simcha b’simcha? Obviously, it was to reduce the costs, but is there any halachic problem? I should point out that the organization organizing it is a well-known one that does kiruv.
There is no halachic problem with different people getting married at the same time, and it isn’t ayn m’arvin… because ayn m’arvin only applies when a specific person has two enjoyments that he must concentrate on, such as if he married the two women during one week, (which is what would have been the case with Yackov aveinu), or not to marry women during Chol Hamoed when we have an obligation to rejoice. However if different people got married I is permitted as long as the brides and grooms were not siblings.
S:A O:CH 546-1 and Taz