I suggest planning more like $20 per meal so that if the venue meals are pricy, they are not going to be short. Boxed lunches are $12.50, so outside meals can be had for less, but cannot be eaten in the venue. Dinners are normally about $20 if they are not extravagant with their choices. If you are bringing a big group (40+), you will want to plan dinners ahead and contact the restaurants nearby to see what they can do to give you a reservation and possibly a limited menu so that service can be faster.
I hope that helps.
Please feel free to reach out if you need further advice (I have done lots of travel with teams, both small numbers and big numbers of people).
Heidi Lovett
coach 417 SKID
Swerve Robotics