I have noticed the same. I gave up on buying my batteries at Costco for that reason.
BTW, I have changed my attitude towards the battery leakage issue. So I can go back to buying my batteries at Costco if I want to. But now I am near a Harbor Freight and they sell similar batteries very cheap. And they put them on sale even cheaper on a regular basis.
What I did last year is on New Years Day I went through my house and made a complete list of all things that use a battery. I noted the size and quantity of batteries in each device. I also removed the batteries out of the devices I knew I was not planning on using in the near future. So I preempted the leakage issue. I also decided which items I was going to replace the batteries in every New Years Day. So last year I bought a bunch of batteries and replaced them in every smoke detector, carbon monoxide detector, remote controls, clocks, backup batteries for plug in clocks, gun safe, red dot sights, etc. I also bought new backup batteries for my lanterns in case SHTF and in my weather radio. I will replace these backups every 2 years. And I also have extras for those items that need new batteries before the year is up. So initially it cost a pretty penny upfront to do this, but I had quite a few extras left over from my initial purchase a year ago that I didn’t have to replenish many batteries this year.
The big thing for me is that I had leakage in my gun safe and it took a lot effort to save the battery box. So now I don’t have to worry about it if I keep up my routine. Also, I had to throw away some good tools that the batteries leaked in an ruined. And I no longer have to deal with a smoke alarm that is designed to only go off at 2am when the batteries die.