Wendy, this problem exists in virtually all fundraising activities. What magnifies your problem is the product being of a perishable nature.
The problem you could have is the negative reaction from the community if this person shouts loud and long enough. Unfortunately, you will probably have that to overcome when you start your next fundraising program.
You can do a couple of things:
1) ignore this person and hope she goes away
2) Confront the issue as if you are walking on eggshells. Meaning, be sensitive to her concerns when stating your side of the story. One way to do this is to write an editorial to the local newspaper explaining your policy as well as the situation as it was played. Only do this if there becomes a firestorm of criticism which may affect the quality of future fundraisers.
Numerous groups will schedule their delivery at the same time the school is having an event, i.e. dance, concert, book fair,ect.
This way they are able to distribute the product when there wil be parents at the school.
Some schools have strict policies regarding delivery. "If you don't pick up your product by the allotted time, it will be discarded and the money you collected will a contribution to the school's PTA/PTO. Then, you are responsible for telling your buyers why you were negligent in picking up your items." Now that's on the extreme end. You will probably have to find some middle ground here.
We have done "top Ten" cookie dough for three years now. We've done pretty good - our first year was exteremely excellent! We only have one date to pick it up and it was between the hours of 2PM and 6PM. Notes are sent home one week before, three days before, the day before and the day of. We also had signs at our car rider pick up location. We e-mailed our notes on the other days that notes were not sent out (though our list is under 100 out of 990 students). We would contact parents at 4:00 PM to remind them cookie dough was in. If they weren't picked up our cafeteria freezer is where they are kep and we remind the parents daily until they are picked up. We only had three parents this year that we had to hold them. Much better than in the past. I guess the key is keep the parents notified when the dough is in. Also, our school is PreK-2 so not all the dough could be carried home by the students. Our general rule is if it 1 or 2 tubs / boxes and it fits in their backpack / satchel, etc, they may take it home. We do document this by a letter that must be brought to school with a signature from the parent stating it is ok for the child to take it home. It really does help in pickup!
When we host fundraisers that require a refrigeration process, ie., Market Day, cookie dough, pizza, and frozen desserts, they are sponsored as parent pick-up events. For the parents that don't make it on the designated day, the items are placed in our PTO purchased deep freezer. It also comes in handy for student birthday ice cream treats. Over the years, the freezer has proved to be one of our most useful purchases made for the good of the whole. Just a suggestion!
We did cookie dough for the first time this year. I would say it was a mixed success. We used Signature and I personally did not like the cookies, but many people did. Their dough comes already formed into balls. Different companies have different products - some come frozen in a tub and you have to scoop the cookies yourself.
The biggest problem is getting the cookie dough home. We delivered it to every classroom and the kids were responsible for getting it home. One teacher forgot to give it to the kids and all the dough was ruined (we replaced it at our cost). Other kids left it behind at after school programs. It was also very heavy and hard for kids to handle on their own (came in boxes - should have had bags with handles for them).
Many schools around here have the cookie dough delivered to the school and the parents are responsible for picking it up themselves. They say it works really well - they make it clear that if you don't pick it up you are out of luck.
We don't think we will do it again as a fundraiser - although we did make over $3000 (school of 900 kids).