My parents thought potlucks or even asking for contributions to buying a keg were tacky. Their reasoning was the same: if you can't afford to throw a party, don't. I don't necessarily agree with that. Sometimes, no one in the social circle can afford to throw a party. Combining resources in that case is perfectly fine, charging admission is not. It makes you wonder if someone is out to make a profit. As to all the other stuff about single vs. couple, prices, etc.: it doesn't matter. People have different attitudes and values about that stuff. I , for instance, detest the stupid games people play at wedding and baby showers. I think they're infantile. However, often, it's not the hororee's choice about how the party is organized and conducted. If you care about the person and want to show your support, go. If not, don't. Our principles about party ettiqutte shouldn't prevent us from being kind. I can grin and bear it for a friend or loved one.