I've noticed that at the end of several MCU films, there'll be a message that speaks directly to the audience. So far I've seen stuff like:
"Thor will return in The Avengers"
"Captain America will return in The Avengers"
"The Guardians of the Galaxy Will Return"
"Tony Stark will return"
Why does Marvel do this?
I understand that it reassures fans that certain [potentially favorite] characters will be seen again, but is there anything beyond this?
What strikes me odd the most is that the messages are about major characters that are still clearly alive, and who have no reason not to be shown again in a future film, so, what's the need for this?
Also, Marvel doesn't do this for every film, so, what makes these different from the rest?