Did email have a policy or guideline to allow a seller to list it products?
Yes.
There are products that cannot be sold on eBay at all.
Obvious examples are tobacco, liquor, firearms and hate literature.
And there are products restricted by the brand or copyright holder.
Tiffany and Louis Vuitton are part of this VERO group.
The seller also has to meet certain requirements, some financial, like having a credit card on file.
Some are based on reputation. For example a new seller has restrictions on the number and value of the products she sells and your payment to that seller is Held against her performance for up to 21 days.
Some of the policing is done by robots,who look for forbidden items in titles and descriptions.
Some is done by members who spot problem listings.
And some are caught when buyers file Disputes against a sketchy seller.
Is it frequently happening to other buyer?
No.
But with 25 million sellers and over 140 million products offered at any given time, even 1% is 140,000 problem listings daily.
Protect yourself.
Read the seller's feedback.
Not just the numbers, but the actual words of your fellow buyers.
Look for patterns: many buyers complaining about fakes or non-delivery. (But remember that some percentage of buyers are never going to be satisfied.)
And if you are finding a lot of problems, change your Search.
The default is Best Match, and many buyers use Lowest Price.
In my opinion, a better Search is Highest Price, because it is faster to drill down through a few dozen expensive but properly described items than it is to wade through hundreds of garbage listings for fakes, spam, or wrongly described items.
