now to give a little background i have worked in restaurants for about 4 years off and on. Both bartending and serving. First and foremost their level of service did seem despicable given your description. Even at the simplest of places, guests should never have to leave their seat to ask for assistance and should be the number one responsibility of the server(s). Having worked in the industry I feel the need to apologize for their ****ty service, it sadly occurs all to often. Either way you get what you pay for in a sense, if you had brought your party to Capital Grille instead of wherever you went, i can guarantee that the service would have been much better.
Concerning the issue of having one big table or a few small tables, it all comes down to the layout of the restaurant and the configuration of tables. Splitting the group up could have meant that you had to take over an entire servers section, which meant that for the entire time you were there, the only tips they would be collecting would be yours. In addition if the managers had assigned multiple servers from other sections to help, that one server would have to split the tip with others who were making tips on top of your big party. Its not the best system but it usually works out in the end and is the most efficient in the restaurant world. This server clearly didnt think he would be making all that much even given the mandatory gratuity and chose to treat you accordingly.
In regard to the times for food and such. How fast can you make a salad? I know people would could probably churn them out in 30 seconds so that they dont look like ****, so 18 x 30 seconds + 2-3 minutes for table preparations (extra or special oils/dressings) + 3 minutes for delivery = around 15 minutes. Given people arent always efficient and precise as machines, 20 mins isnt all that bad for that many salads. Unless of course they were already prepared, in which case those servers just didnt like you one bit
There is a lot that goes into big parties like yours that you dont see and they are annoying in a lot of ways to those serving them. I would never tell you not to tip, but addressing your issues with the servers directly may have been more appropriate. Many managers just dont give a rats ass and are content just yessing guests and moving them out of the restaurant to be replaced as quickly as possible. its all about turnover times to them so your little issues was just that, a little issue. This is all in their view.
I hope this helped a bit, i dont want to try and justify their horrible service or anything just bring a few underlying rationalities of the business to light.
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