First paragraph is false (except your opinion in the first sentence). It was entirely random, you fell on the luckier end of the spectrum. Many players went through 40+ items in at least 2 of the first 5 boxes, which were chock full of junk. Furthermore, if you got unlucky in boxes 3-7 (6 and 7 to a lesser extent due to more actually useful stuff there), you could be grinding a long time due to increasing coin costs. The item grinds are annoying, but they are at least reliable even if your luck is shoddy. The suggestions noted by Drynix and myself would have eased the pain for a great many players.