Some did but it was rather rare. There are a lot of cases of famous people who left/divorced their wives to be with another woman (e.g, Pericles). If polygamy was accepted they would have just married another. read more
The ancient Greek marriage celebration consisted of a three part ceremony which lasted three days: the proaulia, which was the pre-wedding ceremony, the gamos, which was the actual wedding, and the epaulia, which was the post-wedding ceremony. read more