Yes, the ground was cursed, but sin and death and their consequences speak of everything becoming more difficult and unpleasant - including labour. It's not a stretch.
well, I can't go there with ya... I agree that if one focuses on the down side of things, it can look that way...
As for what Adam and Eve got up too. Sure, it's an inference, but it's not a speculative one. For example, Adam and Eve had to have other children for Cain to have a wife when God banished him. It's not difficult.
in my experience, if one focuses on Jesus' teaching 'consider the birds of the air' it can begin to look much differently...