Quote Originally Posted by LilimoLimomo View Post
Not stacking prevents players from simply accumulating them without limit, which incentivizes many players to sell maps lest they entirely lose out on gaining value from their daily map gather. This likely makes maps more accessible to non-gatherers, as well as people who want to run multiple maps, as it not only means there will be more maps for sale, but also means that due to the quantity maps will be available at a lower price.
The value from the daily map gather comes from the 18 hour CD before another map can be collected. Allowing players to stack the maps would increase their value as long as SE didn't remove the CD or otherwise make them easier to obtain.

Non-gatherers already have the opportunity to get one map a week through Wondrous Tails.

I agree that allowing maps to stack to a small amount amount (3 - 5) wouldn't change things in any meaningful way other than being able to keep them in one spot instead of having to put one in the saddlebag, deciphering one and then having a third in character inventory. Definitely would be more convenient when trying to spawn Agrippa or especially Pale Rider.