I understand that the cost per item is the same, but I simply don’t need that many bottles (or whatever it is).  So if I get the bundle, I’m spending more money to have more junk in my household. 
So basically, I’m paying more for the three items that I do need and end up with a bunch of leftover crap. This is not hypothetical. I still have a bunch of leftover stuff that I’m not using in my drawers from scenarios like these.