Went to a boulangerie for breakfast and the waiter went mad at us for trying to pay separately

Hi everyone… just wondering what we did wrong and how can we do the right thing the next time we go for breakfast here in Paris

We are a group of 6 and got some really good breakfast near Opera… but when we wanted to pay at the cashier, the woman attending us went mad as soon as I said we wanted to pay separately. We have no clue why she was like that… she started speaking French and all I could get was “oh, non!!” and she kept touching her forehead and shaking her head like in disapproval.

We didn’t understand a single thing but I ended paying the bill in full myself and left there as quick as possible because we were very nervous. Did we do something wrong? Is it frowned upon to pay separately here?

Thanks

Edit; thanks everyone! Learned lesson, not gonna try to split a tab at a boulangerie next time. Even if the waiter ask us to sit down first.