Same reason there's a correlation between electric car owners and extreme arrogance. They're like the original prius owners from a decade ago, except now they have the internet to get outraged all over now.
The building my company is in install a few electric car charging stations. They also allow people limited free charging time.
We now have more electric cars then there are charging stations, so people are constantly watching for people to leave (like to lunch) so they can grab some free electricity.
So, these electric car owners not paying gas taxes to maintain the roads, they are getting large tax rebates for buying the electric cars, and now are getting free electricity to charge them. Guess that's what is need to make them cost effective.
Can we say free-loaders?