It's simple, go to Old Chicago no time limit on anything.
Unless it's a McDonald's/Taco Bell/Fast-food joint of some sort and you're just taking your food to go, showing up 15min before close is tasteless and rude. That's why she's telling you they're closed, they're "closed" to taking in any more customers because they're closing in 15 minutes. Not difficult to figure out. Grow up.
Please don't say you thought you were going to order food... With a 10p closing time, you should consider what happened in the movie Waiting.
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