This is how NASA got many billions of funding from the USAF for part of the space shuttle program - look through the list of flights in the 1980s where the payload was an unspecified national security satellite. The capability was promised and it was funded for it - but almost never used. The actual ability to grab a big thing and return it was hardly ever used, such as the LDEF mission. It doesn't help that a huge percentage of Soviet satellites that they might want to have grabbed would have been unreachable from a space shuttle launch site (IMINT satellites in 90 degree inclination polar orbits, satellites in molniya orbits, radar naval observation satellites in MEO orbits) all beyond the orbit/delta-V capabilities of a shuttle mission. And of course geostationary orbit where no human has ever gone.