The "lunch and dinner" and expenses argument is misplaced.
As for the expenses argument, that was intially brought up by MoL, a well-known friend of the pilot community.
One could argue that it's better to spend money talking to people than to spend it in court, which should only be a "last resort".
As pointed out before, representation works by meeting people, both to meet members and to discuss policy. Much of the IFALPA member organization's work is done by committees who work out a mutually agreeable policy which is then taken to ICAO for implementation. This ends up on the balance sheet as "meetings" because there is no way to get a lawyer to make ICAO do something. That's the way with lobbying.
All those who think "Lobbying" to be a dirty word should consider that our employers, be it AEA, ELFAA or ERA spend copious amounts of money to convince BRU based as well as national bureucrats and politicians to enact legislation they want. If we don't put up with them, we'll end up with laws made for airlines, not laws made for pilots.
Pilots are one of the best connected professions worldwide. IFALPA represents over 100.000 pilots and a global cooperation like this needs the occasional face-to-face exchange to reinforce the bonds. The fact that humans prefer face-to-face meetings over video-conferences, phone calls or chats is one of the cornerstones of our industry. We should be aware that we need to meet fellow pilots face-to-face from time to time if we want them to assist us in times of crisis.