You regularly see an opponent tutor for a card during his or her turn but not have the mana to use it, so the player passes the turn
Chances are, if there's 20 1/1 Goblins on the board, and 10 other big scary creatures, you'll only be leaving a puny gobbo on the battlefield
(The copy becomes a token.) A resolving copy of a permanent spell becomes a token, so the token isn't "created." Effects that care about a token being created won't interact with a token that enters the battlefield because the triggered ability copied a permanent spell
Go-Shintai of Lifes Origin is marginally better than Hei Bai, Forest Guardian, in my opinion, but its vulnerable to enchantment removal while Hei Bai isnt
they do come with some great accessories and a good selection of cards thatll be ready to go straight out of the box, but $50 or more per deck is a lot of money for players who may only want to play casually
it's in selling the experience of discovery