It seems like many of these prosecutors/plaintiffs just want to go after the largest organizations in a given industry, almost irrespective of their culpability. It seems to me that most 'consumer protection' lawsuits seem to be more focused on obtaining publicity for the lawyers than actually doing anything useful, but getting a few settlements from larger organizations is a lot easier than actually going after wrong-doers, so it is a somewhat sensible strategy if the goal is to 'win' as much money as possible.

But isn't most of the fees a result of the interchange rate, set by visa? The fact that stripe or whatever charges a fee on top, which contributes to the overall rate hardly seems relevant, unless you think all the payment processors are colluding to set their markups higher.