Yes
It depends on time of day. We've walked in before and after a little wait have been given a table. If it's off peak times you should be alright. If you plan to go during traditional meal times I would call ahead.
Yes and no, they say to get one of the cars you need to book and walk ups get the tables. But, I've personally walked up and got a car table. They recommend booking to guarantee you get a car but walk ups get whatever they have, usually the tables.
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