Shorts yea, t-shirts and flip flops no.
We were driving by our first time there and all I had on was a tshirt and shorts. They had no problem with it. I did feel kind of uncomfortable because everyone else was dressed nicely. I asked about our attire when we when at first and the greeter said that as long as my money was green it didnt matter. This put me at ease and we had a great dinner. We will be going back soon.
Shorts would work with a colored shirt or polo. With a T shirt you may feel out of place, but maybe not. I have seen them there, especially if you want to eat in the bar area, which is very nice, too
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