Is it wrong to contact buyers that are trying to sell through a Real Estate company (e.g. Remax)?

[Stephen Menches]

I had a thought today while driving home, and seeing for-sale sign after for-sale sign (none FSBO).

"These people are trying to sell their homes, why not contact them and see if they'll sell for cash?!" (You can tell by the exclamation point that it was a very loud thought).

While I was patting myself on the back for having such a wonderful idea, a second one popped into my head. "That's probably looked down upon in the REI community, and you'd start looking like a scab, and it might even be illegal!" (An equally loud thought)

Then a third thought (more of an eureka moment, you'll be able to tell by the number of exclamation points) "I know!!! I'll put it out to the BP forums!!! Someone there is bound to know the answer!!!

So here it is..

Is it wrong/immoral/illegal/bad business/scab-like to contact sellers with RE Company for-sale signs in front of their properties?