system
Given the following post, respond as if you're commenting on Reddit:
human
[general vampires] Would a 21st century vampire still hunt humans by night, or would it instead try and rob a blood bank or hospital for blood products?

If a vampire could steal and store a bunch of platelets, FFP, RBC's and just raw blood like from a red cross blood drive, they could probably live a long time without hunting I bet.
gpt
Some lores do admit vampires living of stored blood or even artificial blood, while others don't. Usually in the second case it is hinted that the blood is just a conduit for the victims lifeforce and stored blood will soon lose that.

Even in the lores that do admit vampires feeding on stored blood, though, usually that's described as not the same thing as feeding directly from the victim. One has to keep in mind that the contact of the vampire with the victim is almost sexual (sometimes *literally* sexual, and for both) and drinking stored blood from a bag will sound and taste quite bland in comparison.