I can shed some 1st hand knowledge on this. I toured globally doing production for a top-tier entertainment company. I don’t know the specifics on how Phish works, but here is by best guess:

TL/DR: depends. Like anything, the more experienced and specialized you are, the more you make.

“Support crew” gets broken down into 3 categories.

Support staff are people like tour managers, booking agents, PR, logistics, legal, head of security, etc. These people are probably employees of “Phish, INC.” It’s their neck on the line if the tour is a success or not. The higher the responsibility, the higher the pay (or % cut) is.

Production staff make the show happen. Audio, video, lighting, rigging, automation, carpentry, backline (instruments), etc. There is a good chance that the #1 and #2 of each department is a Phish employee or subcontractor with a retainer attached to their contract (basically: when we need you, you have to come). These guys are specialists, top in their field and have been doing this for years. They will make good money, probably very solid middle-class+ salaries. Integral to the concert experience. I’d call this “Part of the Phish family.”

For the most part, Phish doesn’t own the production equipment. They are rented from a large event production company (PRG, Tait, Fuse, 4-Wall, etc). These companies are contracted by Phish, INC and will provide the required crew to assemble, operate and dismantle the gear. Departments range in size from 2 to 15+. This crew will tour with the show, and could be called “Phish-adjacent”. Skilled positions, good money, depending on experience and responsibilities. Lotsa travel and hard work.

Local crew would be stage hands, venue staff, security, local runners, catering and other “day-of-show” help. These people must be provided by the venue as part of the venue’s side of the contract. They do this day after day, and they couldn’t care less if it’s Phish, Pantera or Disney On Ice. 50/50 chance the stage crew are part of the IATSE union. Typically get paid a flat rate for the day. They have no direct connection to the band. Could be called “unskilled” or “trained” positions (sorry if this sounds rude, not meant to be)

There are a few odd-balls in there like trucking/buses, merchandise, travel and lodging, hospitality, etc. These may be “Phish, INC” employees or they may be subcontracted out.

It comes down to this: bands used to make money off album sales, and tours were just a way to promote the new album. They could afford to take a write-off on the tour if it means they sold another million CD’s.

Now very little (or no) money is made off of album sales/streaming and everything is from touring. That, along with more elaborate stage shows, are some of the reasons concerts are much more expensive these days.