I seem to be on the opposite side of many MNers here and I think people have been unnecessarily rude about OP. Fair enough to say YABU but not that she's clueless, crass, CF, lacking class etc
As for people saying it's ok to charge people £30 for an Abba tribute night but not if it's in a cottage.... Or purple who were able to spend £1000 on a night but not charge guests, what's that got to do with anything? Not everyone can. Fair enough you can choose to do something cheaper but sometimes it's nice to do something different as well. No one has to go if they don't want to. Arrange something else with them
In my social circle (appreciate everyone is different!)
Normal to pay for your own food in a restaurant
Normal to pay for a take away at someone else's house
Normal to put money in a kitty for a holiday cottage or similar
Normal to chuck in some money towards a BBQ or 'naice' meal eg at Christmas as an alternative to going out when people found that hard with baby sitting.
If you invite people to dinner, explain that it's catered and are they happy to split the cost then they can say yes or no. As MN always says, it's an invitation, not a summons.
Personally I would be happy to. Ok I appreciate some people wouldn't but I find the level of shock and vitriol and complaints that OP is demanding people do things her way odd.
I really don't see the difference between any other event a friend might invite me to for a birthday that I'd expect to pay for e.g. theatre (if it's a show I don't want to see, I won't go...) Restaurant (if it's food I don't like, I won't go) 'activity' e.g. one of my friends wanted to go horse riding in beautiful countryside. Some of us went and enjoyed it, others didn't fancy it so didn't. No problem.
Same for this, if it was £25 for food I hate then obviously I'd decline, ditto if it was a long way to travel and I didn't want to but I wouldn't have a problem with being asked. Presumably these are close friends OP knows well so she has a reasonable idea of what they would like.