I don't grow palms -- or see any here in the mountains -- but that looks like a severe infestation of scale insects.

And that's about all I can tell you. But you should quarantine the new palms away from your other plants till you're sure all the scale is dead (scale may not look real mobile, but it does spread from plant to plant).

Hopefully someone else can tell you exactly which scale you're dealing with, how to kill it, and what to say to the vendor who sold you infested palms.