Been there though not a birthday..
I was on a course, funded by the Princes Trust (my place anyway, not the others). I was 19, the others were in their 40s/50s, on the course for a jolly mostly.
We all went out for a meal, I had just enough for my meal and tap water, I had NO idea about the whole 'split it equally between us' malarkey, I'd never been out for a meal out with a bunch of bloody strangers before to a reasonably nice restaurant (nothing special... just, nice enough).
It came to £40 a head, I had spent £15, I had pasta, no starter, no pud, and tap water. They all had fucking starters or puds, wine, more expensive mains etc.
One rather repulsive chap (called us all 'girlies', was in his mid 50's big moustache, braying voice.. that sort of thing, I was the youngest there by 25 years) had rather taken over and domineered the whole night and made me feel about 2 inches tall when I said I only had a £20 note on me and would need change. Really laid into me how that wasn't 'proper' and what did I think I was playing at, implying I was scrounging, in that jovial but not actually joking sort of way. No one else said a word, awkward silence... most of them thought he was a riot, except one other lady who was too quiet to stand up to the prick.
Fucking horrible experience. Quiet lady did come back to my room after for a coffee and she was kind, just not up to defending someone against such a bullish twat - thank god she was or I think I'd have quit that day and not finished the course!