Yes and you should always make a reservation on a holiday. Remember to tip your waitress she's still making 2.83 for a holiday so keep that in mind when leaving your tip.
Yes, most restaurant's are open. Most people pay double time EXCEPT wait staff. These people are missing there own Christmas. 20% is normally considered acceptable. I like to leave 25% or more. Making reservations are appreciated but not mandatory. If you don't reserve a table you may have a long weight.
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