Gather and Congregagte

[tedmc]

A group of friends gather/congregate at the hall for a dinner party.

Is there any difference between using the two words or can the words be used interchangeably?
I thought that "congregate" is used for bigger, more formal gatherings like those in a church.

 

[tedmc]

Why is it not appropriate?
In what context is "congregate" used?

 

[tedmc]

I can't see the difference after going through the examples.
Can I have the answers to my two questions above, please?

 

[Rover_KE]

You answered both your questions yourself in your OP:

'... "congregate" is used for bigger, more formal gatherings like those in a church.'