I don't know if it's is
just an American concept, but it seems that Americans have more reasons to want to ER vs other wealthy developed countries where people could ER but don't.
I see so many people joining the boards or starting posts where they talk about wanting to ER because they hate their job, they're burned out, over stressed, just can't take it anymore, etc. You rarely hear people want to ER that absolutely love their job but would rather hang around the house and post on the internet all day.
It seems a lot of members keep jobs they hate because they're frightened to lose their benefits including health insurance. These things are not applicable to everyone, but it's the general perception I get having been a member of the forum for about a year.
I can't speak for everyone, but you might find some reasons why many Europeans don't consider ER as frequently. Most get somewhere between 4-6 weeks annual vacation and are expected to take every bit of it. They don't fear losing their job to someone that will forgo their vacations. You don't have to keep a job you hate for health insurance benefits. You can find a job you like because you're covered regardless of where you work or what you do. Women can take from 3 months to 3 years maternity leave (depending on the country) with no fear of losing your job. No need to rush back to your crappy job 3 weeks after you have a baby cause you have to pay for daycare and keep your health insurance.
Many Europeans pay more into social taxes while they work that gives them a gov't pension when they hit retirement age, so most spend their money on their elaborate month long vacations and toys (kind of live in the present) and don't have to "eat rice and beans" for years trying to save for retirement. Along with the pension, most things (in Estonia anyway) are free for seniors or at greatly reduced prices.
And it may very well be there are some society pressures where you are expected to
do something if you're fit and healthy and ER would just brand you as lazy and not contributing to society (unless, say, you generously volunteered your free time to a worthy cause, which would be seen as "doing something").
So I think that if Americans didn't have such a miserable work life and could get some quality balance, ER would be a much less popular concept than it is. Me though, I'm just lazy so it wouldn't matter either way.