A robot can monitor drug interactions and dependancies a helluva lot better than a human can. I've never seen a robot make a 'human mistake'. There is no pharmacist that knows all drug interactions from the top of their head. They need to consult a computer...so why not skip the middleman?
A computer can flag an elderly customer and a human meeting can be arranged with this person. The need for pharmacists will always be there, but will drastically go down. This is being done successfully in many parts of the world.
25 years ago who would've thought we'd all be dealing with a machine with our money 95% of the time? We all wondered back then how in the world we could trust a machine with your hard-earned money.