I have only ever had seeds in plastic dime bags. Would be shocked if they come any other way.
I have had seeds arrived germinated through the mail. I potted them up right away. Kept them indoors all winter long under grow lights (mine came November).
Pre-chilled I see as a courtesy. Saves time chilling them yourself. Sellers sell to people in the south as well as north, the seeds all have to be the same for everyone.
I guess that question is the same as "why do stores sell beer pre-chilled if you are not going to drink it all right away"? Because it is a courtesy for those thirsty people that want to crack it open right away, while making no difference to those that want to save it in their own fridge.
I also have seeds arriving this week and was shocked at the reverse - the seller only had chilled them for 2 weeks! Now I will have to chill them another 2 before I can do anything with them.
