Do these registrars have time sensitive deals with whichever company owns an extension? For example I was getting .biz 1 year registrations from one registrar for $1.99. and now the priced has jumped to $12.99!
It is pretty much a function of promos, i.e. sale pricing secured from the registry in order to advance adoption of a certain domain extension. Historically this was not a core strategy for Epik but now it is.