Can they really do this stuff?

I was driving northbound on I-95 between Baltimore and Washington, where the speed limit is normally 65 and there is a "construction zone." Now, let me explain, they are building an overpass above the highway, and I drive this route frequently and have never seen a single lane of traffic blocked, and all of the construction is being done off the highway, and there are 3 to 5-foot concrete barriers between the highway and the construction area, and at this time, there was no construction going on, and no construction workers or equipment in sight. So I'm following the 1,000,000 cars in front of me and there are 1,000,000 cars behind me all spaced out at about normal intervals for moderate traffic, travelling north at about 6PM on friday and all going about 62, which is unusual light traffic for that time of day, but nevertheless. Now I am startled by a flash. I've just got popped by a speed camera. At first i look down and go hey I'm goign 62! then I think "oh wait there's construction going on off the side of the road somewhere up ahead" (not wheere the camera is, mind you, but a mile or two up ahead). Then I think "Hey wait I'm going as fast as everybody else." and then I look behind me, and notice this flash off in the distance going off at 10 or 20 second intervals. They were giving every 10th or so car a speeding ticket! Then I get a photo ticket letter in the mail, and it's not even for that speed camera, its for a speed camera on the baltimore beltway, and it says I was going 61 in a 50. 50 mph speed limit on the beltway? Must be a construction zone, right. So, I look at the picture, and I think "when was I on the beltway?," and I realize it was last saturday, and it says the ticket was given near security blvd. There's no sign of road contstruction of any kind in the picture, and I had no recollection of any construction. So I just happen to be going down there a day or two later and I see no sign of roadwork whatsoever, no equipment, nor cones, nothing except there is this little temporary sign that says something like "construction area, 50mph, fines doubled speed camera enforced" Except there is no construction, except maybe from 2 to 4 in the morning, and not necessarily anywhere within 5 miles of the "construction zone" speed camera. I guess the downturn in the economy has the state of Maryland looking for creative revenue-generating measures.