Looks like compared to other ddos vectors it isn't that bad, because you can actually shut them down yourself unlike snmp etc...

Any unsecured memcache server will also allow anyone to shut it down remotely.

https://github.com/649/Memfixed-Mitigation-Tool

This problem will disappear in days when people notice their memcache servers randomly shutting down unlike the other ones where you are out of luck if the ISP doesn't look at their abuse inbox ever.