DY: I don’t think yogurt is cheaper at all, the probiotics aren’t quantified, let alone certified (that should probably be added to the nutrition facts) and most kids aren’t that crazy over regular non sugar laden yogurt.
Even for most adults if you take antibiotics 2 times a day and need to balance it, it wouldn’t be practical, although there are other probiotic foods that aren’t as mainstream. Again, quantification is key. How many live cultures in my Kosher sour kraut? I have no idea if any at all. And the timing (you’re not supposed to take both together) could benefit from prescription clarity.
But you’re always free not to fill it.