What (I think) is suggested by the thread title and OP is quite different from what happens at "every other club". If the Southampton owner is in deed looking to "asset strip" Southampton by selling off their highest value players, putting some nodding heads in place as chairman and manager until that is finished and then selling the club to the highest bidder leaving with the profits from the player sales and club sale that's not the same as Dortmund, Atletico Madrid, Valencia, Sevilla, Arsenal or Spurs. It is something quite different.
Oh, and Dortmund is the club in Germany with the second highest turnover. They will be able to at least compete for the Bundesliga title if they continue running the club as superbly as they have in recent years.
Apparently nobody wants to buy the club for anything near the asking price, so the conspiracy theory is that Liebherr is selling off players to make up the shortfall and pay for their new training ground, investing just enough to keep them up.