[jabart]

Email is expensive, require extensive monitoring, bounce checking, extra storage, opt-in verification. Webhooks are cheap and quick.

1 email is $0.0001 on AWS SES 1 webhook is ~$0.00000083 assuming 512mb for 100ms.

[adrukh]

You are totally correct! But another way in which email is 'expensive' is troubleshooting deliverability issues, handling bounces, unsubscribes, landing in the 'promotions' tab of your gmail inbox, etc.

Webhooks are... easier to consume.