"Sins of a Solar Empire and Bundle
Sins of a Solar Empire and the Bundle
pack are now available for only $19.99
and $29.99 respectively!"
Two prices respectively, two items (both bundles). Yet you're claiming the first price is for Vanilla Sins (which is not mentioned anywhere).
Its a price fix, or the Email was poorly worded (proof-reading and English comprehension isn't too hard a skill). Either way its a mistake.
Edit: Notice the question mark in both the threads title and content, i suggest you learn how to read before suggesting the same to others.