I don't know if the numbers in the comment you're referring to are correct, but let's assume they're close enough and do the math.
If I pay $5 every other day for 10 diapers, then I'm paying ~$75/month for 150 diapers. $0.50/diaper, $2.50/day.
If I take a pay day loan of $30 for a 200 pack of diapers, then I've just brought a 40 day supply of diapers. $0.15/diaper, $0.75/day.
After 16 days I've recouped my original investment of a $30 loan + $10 fee. By the time day 40 rolls around and I run out of diapers, I've saved $60. I can now afford to buy bulk diapers in perpetuity. For every subsequent month, I'll be spending $52.5 less on diapers.
If I pay $5 every other day for 10 diapers, then I'm paying ~$75/month for 150 diapers. $0.50/diaper, $2.50/day.
If I take a pay day loan of $30 for a 200 pack of diapers, then I've just brought a 40 day supply of diapers. $0.15/diaper, $0.75/day.
After 16 days I've recouped my original investment of a $30 loan + $10 fee. By the time day 40 rolls around and I run out of diapers, I've saved $60. I can now afford to buy bulk diapers in perpetuity. For every subsequent month, I'll be spending $52.5 less on diapers.