No no, the issue is the reverse of the situation you seem to be describing. In theory, were GGG to change the drop tables for SSF leagues, they would make items more common and ESPECIALLY currency far more common. Without being able to trade, it doesn't matter if people get several chaos per map in flat drops because they can't flood the market with it.

This is impossible to do, however, because people would just make SSF characters, farm like crazy, stash their loot to an alt and send it to the regular league. The simplest answer to this is just don't let SSF characters ever merge into regular leagues, once you're SSF you're SSF forever. But GGG chose not to go this route. I suspect (I have no proof of course) that the main reason GGG decided to let people quit SSF can go back to regular league is because if people get tired of SSF, most of them will just quit the league entirely rather than re-level and start all over. Being able to transfer to regular league lets them keep playing once they get bored of being SSF. In essence, letting you give up on SSF and go back to regular league allows people to make the mistake of playing SSF when they didn't know what they were getting themselves into and not regret it later.