Probably because they figure it be a one-off at the time. That or the heroes do acknowledge the crossover just don't see the need to bring it up.
I mean, how often does Batman deal with colourful superheroes on a regular basis? Especially those that can bend reality.
If the ending treats it as a one-off at the time then it's good, but some gave hints for the next things without any follow ups ever.
Acesss was the most popular example.
But wouldn't that limit the paying customers?
Sometimes customer don't want buy certain games but they would play it if it's being offered free in their subscribtion plan.
And the money the publisher got was a lot compared to if the game's just being sold stand alone.
Of course this platform holder has got to be big enough to have very lot of subscribers (GamePass, Apple Arcade, and Netflix fulfil this criteria.)
That would piss them off. Not only that but it wouldn't excuse those who already own Sonic Generations. Just because it's delisted, Sonic CD is still in my Library, as well as Sonic 1, 2 and 3&K in MD&Gen Classics.
Yes, they are still in my library too but no new buyers would make their Steam communities dry.
What is an echidna? But a miserable pile of secrets!
"For Sonic to be good, badnicks are absolute necessities in this world."