Am one of the social committee at work, event next weekend involving most staff.
Contacted today by Person A, who has found out they can't get a train home as planned due to engineering works...bus alternative will take several hours. When A told me where they lived I realised it was in the same small town as B, another colleague. B's DP is giving B a lift home.
Explained A's situation to B and said could they offer A a lift - A is very amenable and said they'd be 'really grateful for a lift, no need to drop me at my door, just anywhere convenient in our town'
Response from B was 'Oh that's fine with me, but I can't agree to it til I've checked with DP if it's ok, as DP is particular about who they let in our car' 
I was like this 
Honestly, is this normal? Would other people do this? I know when I was with my Ex it would honestly never have occurred to me to ask if it was ok with him to give someone a lift, nor vice versa. It just seemed so odd....