The blurb on the website seems pretty self explanatory:
We at GMSOG Airsoft need your help in funding a down payment for our new field MACV (Military Airsoft Club Vermont). 2012 was the last year of operation for the GMSOG field, now we seek to start anew as a non-profit organization at a new location but we cannot do it alone.
GMSOG Airsoft was the premier airsoft field in New England. Situated on 130 acres of varied terrain in Charlotte, VT, GMSOG Airsoft was able to simulate many styles of airsoft operations to include MILSIM, historically accurate reenactments, and much, much more.
MACV will be a field for the players, run by the players. MACV will be owned and operated by the GMSOG Airsoft Team and its leader Derek ‘Tiger’ Chace. Our goal is to continue to take airsoft to new levels. MACV will be operated on privately owned property which permits us to build and modify the terrain, allowing us to use our collection of vehicles to give players an experience rarely seen in our sport. With these tools at our disposal MACV will be able to host amazing airsoft events, from small weekend walk-on games up to large scale milsim events. Any and all proceeds made by MACV will be put right back into the field, in the form of new construction, maintenance, vehicles, interactive props and more. Below is our current website, as well as some videos showing exactly why we want to continue what we’ve been doing.
tl;dr: they need help funding their new field (how/what profits from hosting are used/for is entirely irrelevant)
As for the Make-A-Wish Foundation, I've just contacted them with a link to the site; they'll hopefully be able to clear up if this is legit or not.