Why do Catholics & Orthodox "Pray" to Saints?

Because they believe in imaginary beings, same as all other prayers.

Constantine outlawed worshipping false gods so they just started worshipping "saints." It's a bunch of baloney. Prayer isn't just asking either, it's having a conversation with God.

The Bible says you shouldn't try to communicate with the dead.
I see dudes argument tho. But it don't trump God saying don't try to communicate with the dead. Period.

It is because they blended their former pagan polytheist faith into Abrahamic monotheist faith.

Like Simon Templar?

because it differentiates them, at least in their own minds, from UFO believers.

Its forbidden to pray to the dead. Deceased saints are omniscient or have the capacity to hear millions of simultaneous prayers.
Read Deuteronomy which condemn communication with the dead and stop listening to these retards.