Teen bday

My (37f) teen (13f) is wanting to have a bday party at an indoor play centre. Would like her entire friend group of 20 kids there. They will all show up because that’s how this friend group rolls.

If my teen only wanted 6 of them there, I would be willing to pay the entire cost for them. $22 each plus provide them food and drinks (which is byo).

Is it fair that if I say yes to the 20, that they contribute to the cost? $15 each and I still provide food and drinks for them all?

Most of her friend’s families have lavished out on their own kids party costs because they are financially able to.

Feeling unsure about saying hey, you’re invited to a party, come along but you gotta pay $15. My daughter says her friends won’t mind paying as we aren’t as well off as them. It doesn’t sit right with me though.

Edit: after reading all the responses, I’m not going ahead with the centre. As much as I wouldn’t mind other parents asking for contributions for entry, I’ll let my daughter know the budget and she can plan something. She loves independence so I think she will enjoy this idea.