VAT on bar and restaurant bills

In September I went to a bar in Silom Soi 4 with a friend and was suprised to find 10% service charge and 7% VAT added to the bill. Now a restaurant bill from September fell into my hands and I was surprised to find 10% service charge and 7% VAT (when I paid, I only paid notice to the service charge).

I know that some venues add 10% service charge (and I go there only one time), but adding VAT is new to me.

Is there no law that all prices have to be net? Does this occur in other places as well?