Not only have I gotten this question a lot but I myself struggled with this one for my own wedding; so I am going to share it with you and I would love to know your thoughts.
My cousin's daughter is getting married and she and her fiance are paying for most of their wedding; they are definitely on a very tight budget. They really want to be able to invite all of their friends and family as well their single friends with a "guest." She asked me if it would be acceptable to invite single family and friends but not include "and guest" on their invitations? Her fiance feels like they should definitely allow wedding guests to bring a date but she feels like if they do this than they will not be able to invite other people because they will now be obligated to let their single friends bring a guest that they can't afford.
I think this is always a tough one and I have heard many arguments to both points. I definitely think her fiance has a point - it is gracious to allow single guests to bring a date so they won't feel awkward or left out. But on the other hand, I think her point is valid too -- especially if you really can't afford the extra guests. I definitely think it would be much worse to cut people from your guest list just because you can't allow them bring a friend. What I generally say to most couples is that I would deal with this dilemma on a one-off basis. If you have unmarried friends and relatives in long-term relationships than I would definitely consider inviting their significant others. For our wedding, we talked to our single friends and if they were not with someone serious than we let them know that we would be inviting them without a plus one. We did have a lot of single people as well as couples so it wasn't so weird but if you have mostly all couples and only a few single friends than you might want to take that into consideration. If anyone complains, simply explain your dilemma -- it was important that they be there, but that you couldn't afford to invite dates. Then, carefully consider where to seat them at the wedding; you may want to put them with other singles so they won't get stuck at a table of couples. Who knows, two of your guests might even make a match at your wedding!
What are your thoughts?