Hi Tina,
The 24-hour policy is here to ensure we can pay our guides and that we don't block their time for nothing. The tour is at 5 pm, you could have checked the weather app the day before and said, "it's not for me", we wouldn't have been offended.
However, you wanted to cancel 4h before the tour. We offered to reschedule for the next day, and you agreed and then changed your mind again 3 hours before the tour. We offered another reschedule, but unfortunately, you had to leave Paris.
I know the weather wasn't the greatest that week, but come on, it's Paris in December. It's part of the experience, and we would have been smart about it (entering stores, churches, taking the train...). We had another family take the tour that day, and they had fun.
We felt bad that you couldn't follow the tour, so we offered a 50% refund (although we could not have done so based on the cancellation policy). I'm sorry you felt punished, but we're a small business, and we try to be as flexible and understanding as much as possible, but we also have to make a living.