And what makes a magus selling his services as a method of vis collection wrong? It may seem gauche or déclassé to many magi, but I'm sure there are enough (in an Order of 1200) where he could go out and about selling his services, collecting the vis and materiel necessary to study his Art as necessary. Indeed the magi engaging in commerce arguments could include 'well, you make deals with the fae for that vis you use, don't you? How am I doing anything different?' While specialists selling their services in the Order may be the fringe of your Order, it is entirely reasonable that this is not the case in other sagas. In the context of a less powerful Order of Hermes, said specialists would not come cheap, and of course caveat emptor.
I seem to be detecting a subtle undercurrent of my saga is doing it the right way and your saga isn't, and maybe that's why I'm debating this a bit more vehemently. Ultimately good story-telling is about putting obstacles in front of characters and having them solve them. If obstacles that appear to involve commerce and can be easily solved with vis/money the story could be the exchange or the story could be what happens after the exchange...
So, here's an interesting story nugget. Magus is selling himself....who's buying, and how is it destroying the Order. Which major covenants have a secret shame? Here's a clue, they almost all do in some way, certainly the archetypes from each of the Houses have some vested interest in commerce geared to their specific interests. Do Verditius magi sell their wares? (Because I can't imagine a Verditius who doesn't sell his stuff!) Does Durenmar sell access to the great library? Does House Mercere sell information, or at least get paid for the transport of information? Does a (rogue?) member of House Tremere sell himself to be a certamen champion? Does House Guernicus get paid to conduct an investigation (it's been suggested in some of the books that they receive an honorarium from the plaintiff and the respondent/defendant). Does a Flambeau called on to be a Hoplite get paid for that service, or does he do it for the good of the Order, and take the spoils, getting paid on the back end. House Jerbiton will sell Art to anyone who wants to buy, Bjornaer will pay to keep their wild places, Criamon will pay for interesting mysteries and puzzles. Merinitae bargain with the fae all the live long day. Tytalus, well there's conflict in trade, subtle though it may be.