This is true. But law of large number makes such misfortune unlikely.
That said, it is true that as far as JUST getting the charm pack, this is indeed not optimal, thou only barely worth than the deal store. But at the same time, this event provides more value overall, as it gives other stuff.

And then, we move on to the long, drawn out numbers game.

There are 24 spots, of which 5 are text, one is reroll, one is double.

On average, it takes 23 dices to cover each spot once(due to reroll), generating 145 pts. 145 in charm packs is 145/35*100 in value, or 414.28 coupon, which is, indeed, less than the cost of dice, which is 460. Note that this is using the 100 price of the deal store, if we use the 25% "mark up" of the vanilla store, it would be more than 460.
(my personal value was better, but let's not consider that)

At the same time, you would get one of every item on the board. I'm going to use a lower value than regular price because.. well..
a set of lv 2 magatama: around 50 coupon value
1.5 summon and 1.2 seal scroll, let's say 100 coupon value
1 key, around 8 coupon value
5 coupon, 5 coupon value
1 medium refine, 20 coupon value
1 mood scroll, 10 coupon value
1 medium thread, 25 coupon value
1 purification rune, 8 coupon value
I'm going to disregard the lv3 rune pack, teleport, stamina and sage jiraya, as price is difficult there.
that's 226 total. Now, not everything is considered useful. Me, for example, have no use for medium thread anymore. Let's say it's 150 coupon of "useful" stuff.

Then we have the lucky pack thingy.
We get "25" travel of 3.5 average distance for 23 dices (extra travel for free and extra travel for double). That's 3.65 cycles. Let's say each such pack is worth 50 coupons, so that's about 180.

So for 460 coupon, we are getting around 750 coupon worth of stuff, if we use the best of discounts etc. Probably over 1k if they were to be bought "raw". So it is still a good deal overall.