I thought about this when the local news was advertising a blood drive. Would they be asking about vax status? I also have clean blood, but if I needed a transfusion, what would I be getting?
If you have a scheduled surgery where there is the possibility of your needing blood, you can bank you own prior and are supposed to get it back. This arrangement has been known to fail.
If you go to an ER and need blood, you'll get whatever they have (high likelihood vaxxed).