Mrp inclusive of taxes charged

Now a days it is a practice by Medical shops without GST registration, they used to sell charging MRP which is including all taxes. Suppose MRP Rs.160 inclusive of 12% GST they should sell at Rs.142.86. Purchase price of the same is Rs.110 + Rs.13.20 the cost price is Rs.123..20 means profit is Rs.36.80 means profit for single medicine is 29.72%. Is it correct? Where is antiprofiting Rule? There is n numbers of medicine buyers, we should something for this matter. Please guide.