I could have sworn that when I used to place an Illustrator file into InDesign (say for instance a vector 2-color logo), that the colors in that file would automatically show up in the swatches palette in InDesign. It's not doing that for me anymore. Am I crazy and it never did that?
Illustrator has 3 modes for colour swatches
Original colour mode (either cmyk or rgb)
Global Spot Colour
It's only the spot colour that shows up in InDesign as it's a true spot colour denoted by the dot in the corner of the swatch in Illustrator.
Let me know if that helps.