Are you really that dim? Knowing who the seller is, possibly a name already known for either good or bad, can be quite important in subsequent advice. I'll break it down even more for you since you seem to not understand how this can work.
If it's a well known name, or a name that can be vouched for by someone known and trusted, then a logical conclusion not to worry can be reasonably reached.
If it is a well known name for being a bad guy, time is of the essence.
If it an unknown name then here we have the beginning of a reputation for either good or bad.
See how it works?