The SM minimum even on the lowest SETA tour is still above the ASM minimum for a LORT B+/non-rep, not much, but still above.
And, quite frankly, the PSMs who are still taking these tours out still seem to be at the level where they are not working for minimums.
And, to look at the bright side, at least it's being sent back out on a SETA contract. Before that was created there would have been a big giant non-Equity casting call going on right now to send it out, at the same prices, with a bunch of fresh from college kids getting paid $400 a week.
The other thing to remember is that the producers of the tour don't set ticket prices, that is each individual venue/presenter. The producers charge the presenters the guarantee (i.e. how much money the presenter has to pay up front to bring the show in, hoping that ticket sales ending up covering that cost, which they don't always), which is limited to a certain amount based on the tier they are using, which goes for all levels of touring under Production, Tiered Production, and SETA. So producers do make less money overall on these tours, and when they do make more then the cast also sees a reflection of that in the overage share.
It may seem like we are just letting the producers walk all over us, but they have shown in the past that they are pretty willing to just stop dealing with Equity and send out first national tours non-Equity if they think they can't get their money's worth. NETworks did it with the first national of the Trevor Nunn Oklahoma revival, the Cameron Mackintosh revival of Oliver, and The Wedding Singer, and Big League did with the Stroman revival of The Music Man, just to name a few.
Thanks to the SETA contract Equity was able to regain contracts of the tour of Chicago, as well as keep Mamma Mia under contract and send out a few others like Little House on the Prairie.