This is very minor and lighthearted - I'm lucky with the general loveliness of the people around me for Christmas - but this is doing my head in!
Me: I'm getting myself a glass of water, would you like one?
Them: Just a cup of tea please.
Me: Who fancies a beer/glass of wine/champagne/orange juice?
Them: Just a cup of tea please.
Why 'just'? When a cup of tea obviously takes five times as long to prep than proffered cold drink?