To be honest, you need to understand why these “card blocks” take place before making sweeping statements about them.
Many of the commentators here complaining about this melt away in to the ether with short order when challenged to explain further. They may be roughly grouped in to two broad categories:
- Scammers (of all different persuasions) and
- New customers who have not yet validated their accounts but uploaded significant amounts of money for which they have no explanation as to the source.
There is often a clear understandable reason behind account blocks and the complainer does not often tell the complete story. Only the bits that suit whatever purpose they have in posting in the first place 
