In most cases, it's not enforceable
In the software world (market), I think we pretty much live on a honest system.
For some parts of the world, piracy is as high as 90% or above. People don't really care or are unaware of software license at all, not to mention EULA.
For some developed countries, people pay more attention and respect to properly licensed software, but still, we have an attitude of "I pay for the software so I am fine with it." Nobody is actually reading the content of an EULA.
The only times when an EULA is enforced would be in a corporate environment where a large number of licenses are compromised and catch the attention of the owner (e.g. MSFT). In such case, a team from the law enforcement body will raid an office and... you can imagine.