Putting on a show is not rocket science, it is mostly logistics. You have to able to adjust on the fly as things never quite work out the way you plan them, most of the time.
Always plan for crazy and be happy with semi-normal
Cost of shows is always there and if you are going to get in financial trouble, then don't have a show. Most of our sponsors don't really care what category their money is used on, most just want to contribute and have their name mentioned when the awards are presented. Most of the time when sponsors ask for specific categories we give them out on a first come first serve basis and they know they may not get them unless arrangements have been made in advance.
Yes, we have had to combine categories and sometimes we even split them due to the a high number of entries or lack of entries. No one has complained about it to this day.