As the article itself mentions, the Big Bang hypothesis did not become an accepted theory just based on the single piece of evidence that other galaxies seem to be receding from ours. Indeed, the term "Big Bang" was originally coined as derogatory by the famous astronomer Sir Fred Hoyle, a steadfast supporter of the competing Steady State hypothesis [1]. Many in the astronomer community found the idea of the universe having a beginning simply preposterous. However, in the end, it was the model that best matched observations, and thus became (perhaps reluctantly on some people's part) accepted. This is how science is supposed to work.

[1] http://en.wikipedia.org/wiki/Steady_State_theory