"eating a pasty"? What the hell is a pasty? I thought they were those little things they used to stick on strippers' nipples in the old days, only I think those were spelled "pasties", weren't they?

Nevertheless, the sentence "Like those old men you see eating a pasty and shouting with a dog in a pram" does manage to convey what it is intended to, and in a pretty amusing way I must say. ;-)