I also recently received a G day callout promising the callout fee, however I AM in overtime this month. How then would that be perceived if I accepted the duty (I didn't)? For those saying we should "name and shame", how can you tell if that person working their G Day is already on overtime, thus negating the issue of stealing EFP from someone on reserve?
In any case, FO4EVA, the point of the thread (I think) is that you would've been a cheaper option than the reserve call.
Credit to you for not accepting the duty. You're probably smart enough to realise that they would've done their best to reduce your EFP later in the month anyway.