I have a list of list of reasons why I NEVER use the Stripe Bubble plugin - mostly to do with how limited it is in functionality, how inflexible it is, and how it handle’s post-payment flows (i.e. redirecting back to the previous page) - plus I generally avoid using plugins wherever possible, as I prefer to be in control of my own apps rather than relying on other people’s solutions.
Plus, Stripe’s API is so simple, and the docs are so good, it’s just as easy (if not easier) to deal directly with their API and have full control over the process as it is trying to figure out how some plugin works, only to find it doesn’t do what you need it to do - so you end up compromising and changing what you’re doing just to make it work with a particular plugin.
The Bubble Stripe plugin is fine if you want a quick and easy Stripe integration, and what you need is amoungst it’s (fairly limited) features. But if you want more flexibility, control, and the full power of Stripe’s API you’ll need another solution, and for that you’ll need to store the Customer ID in a custom field.