legal doesn't mean right.
I'm a firm believer that every team should always try to win and that shouldn't be even a rule.
i think Bb is created around tanking, not in that extreme like here. But you often have the question to sacrifice games, to build up enthusiam, manage your minutes from your stars(especially during the cup) and training your players(especially off position)
The salary floor is a nice punishment. Now that you say it, i'd probably suggest that a team that forfeits should have a $$$ penalty.
How can not showing up be ok?
i also think that the BB should change something about it, but i think it is more urgent to make it fair for the opponent. I prefer the solution, that they play a "bot" for minutes and training instead.
And the punishment for teams could also be harder, but not to hard cause i think most of the forfeits are due faults etc. then purpose.