Your response doesn't negate anything I said in my post you replied to. There is nothing rude about inviting "___ and guest". Nothing. You can't even make up a reasonable scenario where it's rude to invite single people that way if you don't necessarily know their current relationship situation or what it might be a few months down the road.
I just don't get why the concept so alarms you.
Earlier you said you'd expect the wedding planner who is supposedly running around with a clipboard and a list, to boot out anyone she didn't find on the list... or move them if they sat at the wrong table... That's what I was responding to. If it were my wedding and I found out anyone was treated that way I'd be appalled. The best laid plans can be thrown on the fire before I'd let that happen.
You would be appalled, if so and so decided to sit next to the really beautiful girl, whose fiance had not taken his seat yet and so and so refused to move? Or some uninvited crasher or three take the seats meant for your oldest friends, or your cousin and is then removed ? Well bless your heart.
There are different rules for different kinds of weddings and if you had one ( which you didn't and I guess never would have, but stick with me...), which was a sit down whatever and were being charged per person and the food etc. had all been made, with no spare ones and a crasher or several came, you would be appalled if they were found and ousted ? Wouldn't you be MORE appalled by unconvincing your invited guests?
And yes,"and guest" without naming the person, is frowned upon.