Geoffrey Palcher was brilliant as his fianc headed off for her bachelorette trip. For a pre-trip party, he booked the conference room at American Airlines Admirals Club. He arrived early to decorate the room. It is possible to personalize a celebration at an airport. This is something that most people don't realize, but Palcher was. He was also taking advantage of a service American provides that Delta and United do not.Washington National Airport Admirals Club Conference Room Credit: Geoffrey PalcherThis is a brilliant idea on many levels.Admirals Club members and non-club members have access to the Admirals Club conference roomsWhile members cannot visit the club if they're not flying American Airlines, conference room guests are allowed to fly on any other airline.The Admirals Club will issue gate passes to meet guests, even if you are not flying.Geoffeys fianc Katie, credit: Geoffrey PalcherAmerican Airlines Premium Co-brand (Citi Executive Card) allows cardmembers to add up to 10 authorized users for no additional fee. Each cardholder can also bring in two guests. If there is space, one person could sponsor 33 people in an Admirals Club.For a special occasion, you might consider inviting people to a private space in the airport. This is something that you can personalize for your guests. You can even taste wine from the Admirals Club bar.Which Airlines Offer Conference Room RentalsUnited Airlines has stopped accepting reservations for conference rooms since 2016. Jonathan Guerin, spokesperson for United Airlines, tells me that the privacy booths were created to replace conference rooms. This was in response to customers who wanted more private places to make calls.Delta also converted its conference rooms into seating in its clubs. Business meetings are not allowed there.American Airlines offers conference room rentals at 13 locations: Boston, Washington National B&C clubs, Dallas Fort Worth A and B and C clubs, Newark, Houston, Los Angeles terminal 4 and New York LaGuardia. Miami D30, Chicago OHare H/K and San Francisco. Prices are:Members pay $65 an hour ($90 for more people)Non-members pay $85 an hour ($110 for more then 10 people).You can make reservations at the club by calling Member Services (1-800-237-77971, Monday through Friday, 8:00 a.m. to 6:30 p.m. Eastern), at least 24 hours before your arrival. Make sure you include names and dates of birth for all guests. At the time of booking, payment is required.All non-club members can get free drinks at the bar once they are inside the lounge, whether they fly or not!American Airlines has an under-utilized and under-appreciated revenue opportunity.The Cost-Effective Method To Access A ClubA day pass to American Airlines Admirals Club is $59 per person. However, it allows you to visit multiple clubs in the same day. For $354 per person, a family of six would be able to access the club with no membership. It is cheaper to rent a conference room at the club and you also get private space. This is not just a license for you to search for a seat.You can use the Airline Lounge even if you aren't flying that particular carrierUnited, Delta and American have all imposed restrictions on lounge access. Members can only access their clubs when they fly the airline or eligible partners that day. Lifetime club members are exempted by American and Delta. United offers United travel even to Cleveland-based members, who may not have a hub that makes United travel possible.I cannot use the American Airlines Club in Austin when I fly Southwest. The Austin club was so full that the airline delayed investing in additional space into nearby offices it no longer uses. They converted the conference room into more seating. They also converted their entrance into additional seating. The club was still packed at peak times, even though they increased the number of destinations served from the airport to four.It doesn't work at my airport. However, if you don't have a membership you can still rent a room in the club to hold symposia before you fly on another airline.If you're flying, meet your friends at the gateThese days, gate passes are difficult to find. People will sometimes buy tickets even if they don't intend to fly to pass security. They will cancel the trip to get a refund or a future travel credit. This is not exactly kosher but it's not uncommon. Do not try to use this trick to gain access to lounges. Lufthansa has taken action against anyone who used their lounges in a way that was not permitted by law.It is much more convenient to receive a real invitation that allows you to pass security. Gate passes are not eligible for PreCheck, so you will need to clear regular security and remove your shoes.