There are a lot of people "LOLing" at people who say this isn't standard LP behavior- it very much is. If you suspect something might be up, you assign someone to tail them. You either deter the behavior or catch them in the act.We can't, but there are plenty of people discounting racism as a factor and you don't seem to be chastising them.
It's not that people are discounting racism as a potential factor - but it's one that's unprovable without a pattern from this individual. (Or a singular outright racist action.)