No change. Again. Still?

Once again at Roman's Pizza New Redruth they had no 10 cent pieces for change. This is only 10 cents but there is a principal here. It is mine and I'm entitled to it. The cashier eventually got her own handbag and opened her own purse to give me 10 cents, which I declined. This is not good - it was only 17:15 and I would imagine that many more people would be buying pizza later in the evening. This is my third complaint about this problem at the same store.