There is a difference between having a lot of guests and having the SAME couple over and over again. One is nice. One causes problems.
Again, there is something to be said for a healthy balance. We have a family that we are very good friends with. Generally speaking, we either have them over, or they have us over about 3-4 times a year. In fact, we have a “tradition” with this family where we have them over for the last day of Pesach. The running joke is that we are their “geborkts dealer.”
Agreed, having the same couple over week after week may not be healthy — but I don’t think that just because you have them over once that it should result in a ban from them ever coming over again — even on a semi-regular basis. Moderation is the name of the game.
The Wolf