Ok, i'll give it a last try, although i should be aware of your maximized feedback-resistance....
You implemented this shop with the tabs a while ago, and it was working as intended.
But, many players did not "fully understand" how to optimize the usage of that system, right ?
Your intention was to simplify things, which you did.
But, you also said, that there were people understanding the system and using it "smart".
IF you wanted to help players, why didn't you try a different, more rational approach and give a better explanation to the shop, how to use it and how to optimize the usage ?
You give very good wiki-explanations for many areas, really good in deed.
So, it would have been worth a try, to FIRST explain players how to maximize the experience with the shop, that was WORKING as intended.
Shop tabs could be enabled/disabled with just a checkbox "old system/new system", IF wanted.
Why do you think i am giving you my time and writing all this feedback ? Not because it is so super duper good and better and cheaper than before .... I understand your intentions (which were not mentioned in all the posts) and of course I understand these and cannot argue against, because it is your business model.