This is a case of short term vs long-term thinking.
There are other platforms where users can create tokens for a one-time fee and if bitshares requires "rent" then users will quickly migrate their business elsewhere. It's important in a market to remain open and do things as cheaply as possible. As Sam Walton said "Give customers what they want - and a little more." Bitshares is super efficient and we can let people use the blockchain for super cheap (and still profit). We're happy with the creation, transfer, and trading fees UIAs generate, not to mention user interest and blockchain utility.
Important also to realize that there are 2 types of assets on the bitshares blockchain (besides the core token). UIAs (user issued assets) and SmartCoins. UIAs can be created in a finite amount (1-1,000,000,000), flexible trade fees, and any other parameter you could care to name. Basically UIAs are like assets issued on NXT or wavves or counterparty or ardor or antshares or whatever the fuck else.
SmartCoins are more unique and I think you'll like this: They reduce the supply of spendable bitshares. For example, bitCNY can only be created when someone thinks that Bitshares will increase in value compared to this asset and decides to create a special smart contract. This locks up ~3x the value in bitshares to create one bitCNY. This "smart contract" can be created in the wallet by clicking on "borrow bitCNY".
I know this opens up a whole slew of new questions like
"what happens if the value of collateral drops below the value of bitCNY?"
"how is the price of bitCNY established and maintained?"
There are great answers to these questions, this is not the place. Bitshares has a heckuva learning curve.
Basically you can borrow and sell USD and CNY (and gold and others) with no interest and no counterparty (nobody holds the bitUSD but you). So along with influence over blockchain decisions, this is another reason BTS will continue to grow in value.
Just... hold onto your seat for a minute, there is a lot of excitement going on right now in blockchain world, possibly approaching a maddness phase. The wheat and the chaff are going to be separated. To me, BTC is a crazy bad investment right now, blockchain at capacity, slow and inefficient, terrible governance and toxic community. BTS will never face those problems but crazy will always have its day.