I definitely do not have the same amount of play with my standard bulky Easton skewer. Further, I observed that the shaft diameter on the Streeters skewer is significantly thinner than on the Easton, and I'm suspicious that this is the cause of the extra play I observe.
I suspect the culprit is this: the diameter of the titanium skewer rods at the hub axle ends that sit inside the dropouts is too small, therefore the problem of vertical play between the hub axle and the dropout arises. The skewer axle inside the hub is supposed to keep the hub in place, and the outside washers/nut keep the axle clamped tight against the inside of the dropouts.
The diameter in the middle of the skewer rods doesn't matter (think butted spokes). Rather it's near the ends where the skewer rods need to fill up the inside diameter of hub axle ends. If play exists between the skewer rods and inside diameter of the axles, then the hub can move vertically inside the dropouts.
I call it a design flaw on Extralite's part, and an unnecessary concession for the sake of an incredibly low weight, but this is not the only superlight skewer that creates this problem. Don't get me wrong, weight of the Streeters is very impressive, but I wouldn't dare ride them myself. I wouldn't be as confident in my bike, and its ability to handle what I throw at it without issues, rather due to the less than optimum design of the skewers than their minimal weight.
If you could somehow fill up the space, your wheel flop problems should disappear, but then that would add weight and this is, after all, weightweenies!!