That's a feature and not a bug, because every time EC is bought for whatever currency it is created through a FCT-EC-conversion-transaction. Factoids become Entry Credits and those Factoids are burned. That has many advantages at once:

1. It connects the value of Factoids deeply with the usecase. The more Factom will be used, the more FCT's will be burned
2. Those who want to use Factom don't need to handle a cryptocurrency and can avoid potential regulatory problems
3. EC's have a fixed price, so that customers also don't need to be concerned about volatility. Purchases are predictable
4. EC's can not be transferred, only be used as "one-way-tickets" to use Factom.
5. That is also something like a natural security-layer, because EC's are not even interesting for hackers.

6. Theoretically it's possible that Factom-users buy EC's from everyone who holds FCT or has access to and wants to sell them or they buy FCT themselves first.

There is a good article about the two-token-system: https://factomize.com/the-genius-of-the-factom-two-token-system/