My 30th was 10 years ago and we had a big house party. Most of our friends were struggling artists / students. We spent about £200 on meat and beer and invited everyone round (granted, not a surprise, buy hey!). People came from all over the country - good opportunity to catch up with old mates.
Asking for money is plain rude and she is clearly not in synch with the rest of humanity. That said, in your case I'd still cough up and go. Then pebbledash the toilet.