Agree 100% and I hope someone can direct the new owner to these comments. That cafe is in a perfect spot to catch users of platform 2, and if I were him, I'd concentrate on catching that passing trade. Get a nice A-frame blackboard outside the shop to let people know he does great coffees. Do a good line in nice breakfasty things to take away - croissants, muffins, bananas. Then take out sandwiches from mid-morning, especially hot ones (paninis, toasties etc) to catch the off-peak commuters. If I have a lunchtime meeting at Victoria, you can bet your bottom dollar I'd go to a cafe like that to get something nice for lunch to eat on the train.

And yes, get rid of the shutters and make sure you have information in your window that lets the evening commuters know what you could be offering them the next morning.