When I worked in Germany the company I worked at did that. You had until the end of the first quarter of the next year to use all of your vacation days. If you still had vacation left after this date, they forced you to take them until the end of the second quarter - this was frowned upon and managers made sure it wouldn't happen.
I'm not sure if this is a law or just something the company did but the problem here isn't peer pressure. It seems to be part of the business model of Japanese companies because implementing and enforcing such a policy is easy.