My son and his wife are having a group gathering after their luncheon reception for their close friends only, and my husband and I have been invited to attend, as well as the bride's parents. The other relatives have not been invited. I feel that it is not proper for us to leave out of town 'family' guests to fend for themselves - and my son has said that he feels it is not his role to entertain the out of town guests (which I agree). Bottom line - I do not feel that my husband and I should attend the "post reception" party, and that we should spend time with our family who traveled here for the wedding and will not be leaving till the following day. Isn't it our place, as the groom's parents, to make arrangements for family who traveled here and will be staying another day? Thank you for your time!
Hopefully this gathering isn't being hosted by the couple as this would be impolite to the wedding guests. All wedding guests should be invited to the 'entire' reception. If this is something that isn't hosted and there are no invitations for it, it should be fine. If guests are invited, all wedding guests must be invited.
You are not responsible for making plans for the out of town guests. It is a nice gesture though. Plus, if you attended this post party, it would seem as if it is part of the reception.