I, too, experience the same frustration with read-only business card notes generated with the Android app. I have totally given up on using the Android app for that purpose. Instead, I use my Fujitsu Scansnap scanner to scan business cards straight into Evernote as JPEGs. Evernote's OCR of the JPEGs makes the business cards discoverable via search.
This allows me to insert an Evernote link (and include other written observations about contacts) from those scanned business contacts to meeting notes. That way, I can trace those business card contacts back to a meeting they were in. I cannot codify this contact -> meeting relationship using the read-only business card notes. Why the Evernote app made the business card notes read-only is a mystery: a bad design call.
The drawback of this approach is that there is no copy-and-paste of email addresses and LinkedIn connectivity that you would get with the Android app business card scan. I just wished Evernote didn't make those card notes read-only.