I think they have a lot to put up with. I have just ordered repeat prescriptions (online), and saw that one item was not available, so sent a message asking why I couldn't have it, as it was due. As soon as I pressed 'send', I realised that we are still in January, not February as I'd been thinking. I immediately sent another message apologising, but if I hadn't realised it would have fallen to the receptionist to call me and say I couldn't have the drugs I thought I needed and had been made unavailable.
However. I really do think that there should be much tighter training about confidentiality. Not just in GP surgeries, but in hospitals, where they are often worse, in my experience. They often shout out names, dates of birth, addresses etc in front of others in the waiting room, and the safety glass (which I understand they may need) means that older people in particular often get fairly private details discussed loudly enough for others to hear. Now that so much is done by phone, I have had several calls when I've been on a bus, or in company, and have had to cut them short when they've launched into a conversation that I didn't want to have in front of others.
A quick 'is this convenient' before starting the conversation would go a long way.