Fired Up Ceramic Cafe in Petts Wood, Orpington

Had a terrible time at Fired Up today. I took my 3 yr old son to Fired Up today in Petts Wood, and one of the member of staff was very rude, insensitive and inappropriate to us.
My son has always enjoyed painting, so he started painting straight away. He loves painting with black so he started with black. I was just taking my coat off as my son painted away, then a member of staff shocked me with a very loud, impolite and patronising voice aross the table through all the other children and all my friends (it was a birthday party): 'Excuse me! You will have to pay for that separately, Do you know that?! It's not part of the party deal! And if you paint with black, it will not come out very nice!' - everyone went quiet, and my son stopped painting with a shocked face. I was also shocked - nothing to do with the message she was trying to deliver, but the way she said it. I said I'm fine with whatever color my son wanted to use, and I will pay for it separately in the end if that's case. I wanted to say more, but I didn't want to ruin the little girl's birthday party. What made me feel very upset was that, for the rest of the party, my son never touched the color black again! After the party, my son said to me that he did not like the way the member of staff spoke to us, and it made him feel ashamed.
So, I would NOT recommend Fired Up pottery painting studio to anyone who wants their children to create art freely, to express their very own personality through painting, or to simply have a good time. Very very disappointed and upset.