they do just not in or near temple or guruwaras. But can at reception or sometimes in tents but not on the religious grounds. Though some opt to have vegetarian after the religious wedding ceremony even its in a hotel in case having evening reception and then veg or non veg at main reception.
In summary most that I have known or seen who have weddings in a temple or guruwara later serve langar/lunch then its vegetarian.
I was talking about normal banquet hall weddings not mandir.
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