They should have left a path on the left side as you go up. Reason being it's easier to balance going up than going down, and the majority of the population has a stronger right hand to grip the rail. Personally I'd ask them to clear a path, because they might just have been stupid and jump to it, but if they don't I'd go shove a few out of the way on the bottom step with my foot, giving them time to change their mind before I continue on up, leaving bottles rolling down in my wake.