More clubs need to be structured as non-profit. It's not like they're making any, anyways! And those that are can simply reinvest in the club. The economic advantages usually outweigh the negatives (which are?), especially for corporate support (here it's tax-deductible if the sponsored organization is non-profit).
The Seattle Sounders have operated under a similar structure since 1994. With far lower attendance than Montreal, the Seattle club still returns year after year to play again.
No, bad idea. People won't invest millions and billions to get a warm feeling inside in return. In the end, the owner simply has to put himself on the payroll and give himself a raise each year in accordance with how much operating surplus there is. It's a shady practice at best.
1. Who's investing billions in the USL? 2. Simply put yourself on the payroll if you're the owner. It's not like there's that much profit getting generated. Most owners operate at a loss anyways (there are what? 3-4 profitable teams in the USL1?), so they might as well try to attract better sponsorship revenues and make their dollars go the furthest through a non-profit structure with tax breaks and exemptions.