Nonprofits automatically get 2.2% with no minimum volume, and in-person transaction with a PayPal Here dongle on your phone/tablet automatically get 2.7% flat with no minimum volume.
PayPal's open pricing was part of the inspiration for opening up our pricing tiers. PayPal however sells directly to merchants. Balanced sells to marketplaces, which benefit from the aggregated volume of merchants on their platform, hence the higher transaction volume criteria for our tiers.
* http://blog.balancedpayments.com/volume-pricing/
* https://stripe.com/us/pricing
* https://www.braintreepayments.com/faq control-f pricing
TL;DR: Everyone has 2.9% + 30ยข on their page, Stripe mentions to email them for a discount if you're doing over $1MM/year.