cash, travel, VIP
Couldn’t they conference on the internet and spend all that money in the research lab?
Actually, getting out of the lab, meeting other real humans, talking to presenters at poster sessions, and getting a far-flung team of collaborators all into the same room is the best thing you can do for a project....
If it is legit research on a legit project with non-bogus funding, do it right.
Ever heard of SKYPE?