Just to be clear you're talking about the TF Collection #12 vs Encore #10 right? Not sure if it the TF Collection #12 had a small run or not but it does include a 6th figure and was released a few years ago. As opposed to Encore #10 only having 5 figures and released a month or so ago. Plus I think there are more fan favorites in Collection #12 than what Encore #10 has.
Because one set was made 5 years ago and is totally different other than bumblebee... ( less paint on him too) And one came out a month ago and is still readily available.
Yes, they are different I posted a gallery. It is more expensive becasue it has been out longer and that set of bots is desired more. HERE
The TFC minibots are made in much smaller quanteties, this is confirmed. The encores are all well made in large quanteties. Then it dosent get cheaper its been out for 4-5 years ago