If you're copying/pasting vector files, placing a vector file in your InDesign layout that is an EPS or an AI file, adding shapes within InDesign, or converting type to outlines, then in5 will export them as raster graphics using whichever Image Quality setting the export is set to use.
If you'd like to include vector graphics in your output, you can instead place an SVG file that you can save from Illustrator.