i think it's tacky to have a party for the sole reason of getting yourself and your roommates fed for an extra few days free of charge. And this kind of invitation sent in the spirit of "hey, I don't really care about you or want you here except to the extent that I can get you to bring me some free food and drink to my apt." is what I was referring to as "tacky." I never said that asking to bring both food and drink was necessarily tacky. The first time i read the invite it struck me a little off that I was asked to bring both - that's a little much imo - and it reminded me of my grad school brother and his roommates inviting anbody they had an email address for to their apt. for the sole purpose of getting a bunch of free booze and meals. And that is tacky to put it mildly.

Thank you for the comments; they're all helpful. I've attended few potlucks in the recent months but they were either at smaller gatherings of better known friends & family or the hostess requested only a dish that would accompany a Greek buffet or something specific. In this case it seems cumbersome to bring both a dish (desserts not really welcome in this case) and drink. It's not the cost that rubs me the wrong but always thought it a basic faux paux to ask your guests to provide drinks let alone all the food. I could never send out an invite that asked for more than a favorite dish.