Ask HN: Should I generate passwords for users?

I'm working on a new site and considering using Stripe Checkout for payment. However, you can't add custom form fields the Checkout, and that means the user would need to enter their email & password on one form, and then their payment information in another. I'd rather have it be seamless.

I could generate a password for the user, and email it to them. It would lead to stronger/better passwords, but I fear it would just anger users who would want to change it.

Anyone gone the route of generating a password for users? What's the experience been like?

https://stripe.com/checkout