I dislike how Zen (and many similar cases, not picking on Zen here) report being not for profit or transparent, while the auto-recharge mechanism guarantees they are sitting on a float of at least $5 per account, and presumably an average of at least $10. That's something like 50 cents of interest income per year per account. It's not nothing and it's hardly egregious fraud, but I feel if they will do this when it's obvious what they're doing, what other corners might they cut

Honesty as a marketing strategy is really undervalued in cases like this