Not received full amount for claim

My handbag was snatched at a shopping mall in Port Shepstone KZN. I was insured for all Risk to the amount of R 10 000.00 and specified 2 cellphones to the amount of R 6 000.00 each. Contents in handbag is as follows: Make-up, perfume,sunglasses,purse, Fossil watch, Tom Tom GPS and Ipod. I asked for a claim form, in which I included quotations on ****** items, Ipod excluded could get no one to give me a quotation on an Ipod. They did pay out R 7 900.00 but the claim was for R 10 900.00. They refused to pay me out for the GPS the reason they gave was that a GPS one normally don't carry a GPS in a handbag, the reason it was in my handbag was that I wanted to upgrade the maps. 2. They did not pay R 6000.00 for the cellphone but replace with a phone for +- R 2350.00 but I paid a premium for R 6 000.00 per phone. I am totally disappointed as to the pay out of the handbag and contents as well as the cellphone. So why do I pay for Insurance if they don't pay out for what I'm covered for ??....