you would be right in your logic if was actually possible to buy directly green bells somewhere, but since is not possible then if you want to buy them directly then you are compelled to spend that quantity of ingots.

Doesn't matter that you get them as a collateral rebate, right now if you want 1 green bell you are compelled in recharging 70-80 ingots and also in spending them in things that require you to spend ingot only (that are very limited and generally bad options if you have a ton of coupons hoarded and you do not want to spend them now...)

That said, even if was possible to directly buy them somewhere (so if you were right in your explanation) they would still cost too much for what they are worth (1 charm pack costs 60 points, how 1 single green bell may cost 40? when 10 blue + 2 purple are worth as much as 2 charm packs? Means that in the best case scenario 1 single blue, that is the higher tier version of the green, is worth 10 of that currency and this is by considering the purple as if they had the same value as blues (60*2/12 = 10). How the lower tier item may be worth 4 times the higher tier one?).

as I said in the reply to jinga.

1 charm pack is worth 125 coupons in the common shop, but in many events they are available for 100 coupons, so lets consider this one the value of the item.

In time limited recruitment event 1 deluxe bell pack costed around 250 coupons (that we may consider the basic value of the item, so konoha gift shop actually had it on display with a 10% discount).

So is acceptable to consider that 1 deluxe bell pack is worth as much as 2.5 charm packs.

This means 150 currency of this colored baloon event are worth 10 blue bells and 2 purple bells.

Even if we considered blue and purple bells on the same value tier (that is like evaluating medium thread as much as advanced thread...) means that 1 blue or purple bell is worth 12 of this currency.

Green bells are the lowest tier so at most they are worth as much as a blue bell (but is reasonable to think that they are less worth than them).

So the acceptable price in this currency for 1 green bell is at most 12 (but more likely something around 6-9).

Since 1 green bell costs 40 means that in this event those bells are on display with a price that is in the best case scenario 3.5 times higher than their real value (but more likely 5-7 times).

If we evalue the fragments on display in this redemption shop by using the same method we see that the value of them is:

edo roshi 200 coupons

edo deidara 217 coupons

sasuke susano'o 533 coupons.

as we can see all those evaluations are in accord with the average value of them showed in other events (with at most a difference of +/- 10%)

myoboku grasps, instead, are evalued 25 coupons, so they are actually here with a +100% value in comparison with lucky board and with a +40% in comparison with great plates.

ty, i'll do it (as usual) :-)