You definitely don't need it. It's personal preference.
FWIW I gave birth to my son at the end of January 2009 and I'm in Ontario and we didn't own a bucket. He went in a True Fit from birth and I don't regret it at all. It really wasn't a big deal (and I too had an older child to get in the car as well, mine was 2.5 when DS2 was born).