Why don't the vending machine in the past have been developing together

Actually the vending machine is almost 20 years in our country, and in the past, many of the vending machine are using COINS notes for payment. And because many uncivilized behavior, making the vending machine often hurt, there are other reasons, for example: some street punk to the small drink a few dollars, has carried on the damage to the vending machine, and many vending machine quality problems, such as consumer payment did not appear in the vending machine goods, vending machine can't to identify COINS, without change, and so on, all makes it hard for the vending machine has been developed. There is thread hanging the money into the machine inside the behavior of commodities, like a coin notes with garbage malicious behavior, it's all a vending machine is damaged, good makes the image of the city, because of a broken vending body reveal the quality of citizens. Other vending machine operators compared to the supermarket, purchasing quantity is little, accounts for less than obvious advantages in commodity prices. From the operator's point of view, each three or four ten thousand yuan worth of vending machines, in order to achieve scale operation, if there is no instalment will be difficult to pay huge fees, it raised the barriers to entry for operators. For consumers, brush calorie of consumption or mobile payment will make the vending machine use more convenient, thereby greatly improving the utilization rate, but this means impossible to implement on a large scale in China at present, single cause inconvenience in use of means of payment. Can provide operators fewer items, only beverages, small food, cigarettes, etc. Of the few.