They used Hook (aka, the writers) to counter Regina's ability to teleport around. Apparently, doing so is somehow more dangerous than just stumbling into the same dangers with lots of stomping and caterwaulin' as they "sneak" through the jungle. He didn't say there was anything stopping her from doing so, just that doing so would guarantee she land in a pile of poisoned plants or some other dastardly danger of the island. Presumably, Rumpelstiltskin knows this as well, what, being just as experienced on the island as Hook is.
Idiotic, yes, but that's what the writers have decreed to be fact. Thus it is.
And I agree, the tedious flashbacks to the past to fill out an episode is really getting old, especially when its the same thing over and over. At least we get to see Snow with some hair. So there's that. (Why the fuck hasn't she grown it out since the curse broke? She looks ridiculously horrible with that 'do.)
Then again, even in the Enchanted Forest, I can't even fathom how Snow was supposed to be more attractive than Regina, either. 'Cause, damn. (I seem to have channeled Will Smith there at the end.)