Although we don't solicit donations, people usually want to contribute.
That's not an issue really, so long as your not soliciting. I assume the event is basically for entertainment, such as a monthly get-together or something of that nature. From the IRS perspective, any monies "contributed" towards such an endeavor are considered a gift to the recipient. As the recipient, gifts are not taxable or reportable on any tax return.
Now if the amount of a gift given by any one person in a tax year exceeds $15,000, then the giver (not the recipient) is required to file a gift-tax return with the IRS. I won't get into the specifics of that requirement because I seriously doubt any one individual "contributes" that much in a tax year. But even if they did, you as the recipient don't have to report jack squat.