I see where you're coming from, but I find the receptionist relatable too. You have no idea how many ***** they have to deal with, who show up unprepared and who don't know their own **** from their elbow, what their GP's name is, what time their appointment is, sometimes even what day of the week it is. It is annoying and exhausting to deal with. It inevitably reaches a point where they want to 'teach people a lesson' by dishing out the kind of treatment that you received, because that is ultimately how people learn to value others' time.
I get edgy when someone starts a conversation with me and they're like "Uuuuggh I forgot what I'm doing here... [insert awkward pause]", when I have 10 other things to do & people to deal with. Come back when you've collected your thoughts. Respect others' time.
Imagine it another way... that it is rush hour and you are stuck behind someone on the London tube who can't plan 1 minute ahead in their life and get their Oyster Card ready whilst they're going up the escalator, and instead gets stuck at the turnstiles whilst fumbling for it in every pocket or in their handbag, and won't even get out of other peoples' way in the meantime. And all that whilst the crowd of people is piling up behind them and turning the whole scene into a moshpit. *** right?