There is no 专业 in MBA program. Only one application, that's all. However, you can choose concentration, such as marketing, finance, etc when you're in b-school. Without W/E, it's very difficult to get admission in good schools.
The quick answer is 'yes', but very rare. For top-20, maybe 1% w/o W/E, but remember those are from top-3 universities, with top GPA and tons of accomplishment in school. There will be more chance for >20 schools, and if you go on to >50, chance are not bad. However, without W/E, you pay the money, then get jobless after 2 years. I don't see any value added.