Workers surveyed for the Expedia said there were many reasons they stayed stuck in the office. Many said they were stockpiling days for the future, some said it was too difficult to coordinate time off with family, some planned to cash-out vacation days and others did indeed cite financial worries, workplace insecurity or a mean boss. And 11 percent said work is "their life" and it's hard to get away.
Another study released earlier this year by the Center for Economic and Policy Research noted there is a wide variety within the U.S. when it comes to who gets vacation days at all. "The United States is the only advanced economy in the world that does not guarantee its workers paid vacation," according to the "No-Vacation Nation Revisited" report.
While the average U.S. worker in the private sector gets about 10 paid-vacation days and six paid holidays each year, 23 percent of U.S. workers get no paid vacation at all, according to the No-Vacation Nation report. And while 90 percent of high-wage earners get paid vacation, only 49-percent of low-wage earners get any.
A separate study of small business travel found that some workers are nailing on vacation days whenever possible.
This survey, conducted earlier this fall by Wakefield Research for Best Western International, found that more workers are mixing business with travel. Just over half of the respondents said they are likely to to pay out of pocket to bring a friend or family member on a business trip. Of those surveyed, 46 percent said they are likely to dip into their own pocket to extend a business trip to turn it into a vacation.
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—By CNBC's Amy Langfield. Follow her on Twitter at