Thoughts on an increasingly common play. Open complete from SB?

[JKDStudent]

So as I play more and more 1/2 full at Party, I've noticed this happening more and more. It gets folded around to the SB (which immediately tells me to start looking for a new table), and the SB completes.

Now the first thing that comes to mind here is that the person actually has a good hand and doesn't want to raise for fear of folding the BB. Also, I've seen many instances where the SB completes and then bets the flop, no matter what it comes. This would appear to be something of a, "I'm stealing, but don't want to look like I'm stealing," play.

However, I just set up a filter to look for any times this happens. I only got as far as the c's in my database (I got tired of scrolling), and the instances I came across disagreed with my observations. It seemed like almost every case was a matter of the SB having a crap hand. And there was also no bet on the flop from the SB without a legitimate hand.

This seems like a pretty odd play to be making, and it makes me more wary than a blind-steal. What are your observations and general thoughts on this play (aside from it being dumb)?