Looking at a couple other games I have just started playing, I think Runescapes items are priced lower. Look at Path of Exile. Sure they have couple pets you can get for 5 dollars but most of the items are prices way higher than the equal item on RS.. for instance. wings, and full outfit and most pets. Portal or teleports are for sure lower on RS.
Im sure compared to most games they are pretty equal in price.The richest person is not who has the most. It is who Needs the least.