[dijit]

there are companies that pay for being on-call and if additional sums if you get called.

source: I work for Ubisoft and they pay me for being on-call and pay me per hour for when I get called.

[toomuchtodo]

I believe they exist (as you mention) but it's not as common as it should be (as it would if labor law required it).

[scurvy]

This probably comes from Ubisoft's French roots. It sounds like a very French attitude to take towards being called after hours (which is illegal there).

I like that they do this for you; good on them!