Inviting people to husbands birthday celebration

I'm planning to celebrate my husbands birthday at one of our local nightclubs and invite our friends. My husband paid for all of them when he celebrated my birthday but this time around we cannot afford to pay for everyone. Do I have to pay for them to enter the nightclub? Would it be rude if I don't? If it is, then I have to figure out a way to pay. But if it's not, how do I go about telling them they have to pay on their own