Use of Garda resource

Not really sure where to post this one - but I thought it interesting that on the way in they were discussing the lack of resource in the Garda to police the new "sub-culture" as was required in the Phoenix Park (Concerts) and every other weekend in major cities - as they were discussing this, I passed a Garda sitting in his car clocking drivers between the 80 and 120 signs on the exit of the M3 toll (my father was recently caught and fined/points from there). I am all for road safety - but what is a Garda (and car - they could do with the car in Donegal) sitting out trying to sneakely catch drivers (he was about 30 yards inside the 120 sign where it was 80) for....