This all happened a while ago, but the bus threads have reminded me about it...
Some months ago, I had a day out with DD (then about 7 months) before before I went back to work, and got the bus to go to the big city. On the way home, I was a bit late getting to the bus station so there was quite a big queue in front of me (I'm used to the train for going to work, but the buses are cheaper if you don't have a season/friends & family ticket - problem is that I forget the bus times).
Now, our local buses have 2 spaces where you can leave a pram unfolded or park a wheelchair, and one of these spaces is better than the other because it's the dedicated wheelchair space so has a bar to stop the pram/wheel chair from moving out into the aisle (other side is just folding seats).
When I got on, there was an older couple sitting in the seats facing the wheelchair space so I had to park the (big travel system) pram on the other side next to the folding seats. It was the first time I'd had to sit that side and I realised that I couldn't lock the brake on both sides of the pram because of a barrier between the seat I was in and the folding seat section, so I was going to have to hold onto the pram all the way home to make sure it didn't swing out into the aisle. Also, it was one of the first times DD was forward facing in her pram (car seat part which allowed rear facing was in the car), so I was also concerned about DD spending about 30 mins with me out of sight because I was behind her (yes, she's my PFB).
There's only 1 stop after the bus station before the bus gets on the dual carriageway, so when the bus pulled out of the bus station and I realised I was going to have to sit on the edge of my seat clinging to the pram all the way home, I turned to the older couple and said "Excuse me, would it be possible to swap seats when the bus stops so I can put the pram safe in there (pointing to wheelchair space with bar which helps keep pram/wheelchair from rolling into the aisle)". The lady turned to me and replied quite shortly "No! He's had a operation on his back", turned back and spent the next 5 minutes muttering to her husband about me being rude & cheeky for asking to change seats.
Now, WIBU to ask to put a pram that I had no option to fold down (because of shopping underneath and not possible to do one handed while holding a wriggly 7mo DD) and which was keeping my DD safely secured into a space where I could be sure she would be safer? If it was a question of leg room, both pairs of seats had the same amount of extra leg room.