I suspect the, "too good to be true" law applies here. If any offer appears to be too good to be true, it very probably is.
There could be all sorts of reasons why Quark/Adobe are unable to shut down the questionable software dealers. They may be out of any effective jurisdiction for example, or they may not actually be selling any software, just taking people's money.
I wouldn't touch it with a barge pole, or, indeed a cliche.
Phil
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Sent on the move......
Phil Ward
Skype: aphilw
• Freelance writer and product designer.
• Consultant Designer of the Acoustic Energy AE22 nearfield monitor.
• Contributor to Sound on Sound magazine.