silverx2c & XueLun,
Maybe i can help you to explain the vegetarian and muslim eaters better.
There is actually no additional cost required for vegetarian and muslim eater because they still charge as per head count. The additional cost comes up when you have less people in a table to share the table dish which is intended for 10 person.
For example, if you have 9 normal eaters and 1 vege/muslim eater in the same table. If your table is $718, you pay $718 + $71.8. This is because the table dish is always intended for 10 person, now you have only 9 person to share the 10 person food, and an additional one head count for vege/muslim eater. However if you squeeze 11 person in a table (consist 10 normal eaters and 1 vege/muslim eater), you also paid the same $718 + $71.8 as you have 10 normal eaters eating the table dish intended for 10. If you prepare a table of 10 vege/muslim, you pay the same per table cost of $718 only.
However, please note that if you put a vege/muslim eater on a normal table, the muslim/vege eater will only get 5 dishes. If you prepare a table of 10 vege/muslim, they will get 8 dishes instead of 5 dishes.
Please also note that unless you have a full table of vege/muslim eaters, then the food is halal certified. Otherwise, a muslim eater having his meal with 9 other normal eaters will have his food serve by the hotel (with no pork and lark). This is because, if you have a full table, they will get outside caterer who is halal certified to serve the food. The hotel restaurant obviously is not halal certified because they serves liqour. You may want to check if it is acceptable with your muslim friends. Esp. for Sept wedding couple, it is the month of fasting, they tends to be more particular about it during this time to be halal certified.