jeepers, I'd be in trouble if it was me. I would have said "hey, I'll just pop your pram over here a bit so I can get through" and I would have said it as I was moving it. I had no idea that would be offensive to anyone, nor that touching anyone's pram would be offensive!
I am pretty relaxed about stuff like that though. When my DD2 was about 10 weeks old she was screaming her head off in Aldi while I was trying to pack my groceries. A young bloke, about 23 or thereabouts, came and asked if he could pack my groceries so I could pick up my baby. He then commented that he loves babies, so instead of him packing the groceries, I let him hold DD2 while I continued doing it. I get the distinct impression that is not something a lot of other people would do if they get upset at the idea of someone touching their pram!