This is the exact opposite of what the economy needs. Let me try to explain what's happened to the economy (and keep in mind this has been happening for years):
In a nutshell, the economy is amassing tu much faster than it can get rid of it. That means every day there is a growing amount of tu floating around in people's accounts. And that in turn means there is incredible inflation, because 100,000,000 tu simply doesn't mean so much anymore.
Now you might be thinking, "But flammable, I just spent 100,000,000 buying this creatu and now I'm broke. How can you say 100m doesn't mean anything?" Well, where did that 100,000,000 go? It just went to another user, so it's still floating around in the economy. Now imagine this scenario: you buy a pet from another user for 100m. That user goes and buys a pet from another user using that 100m. Then that other user goes and buys a pet from yet another user. The tu is just changing pockets, but it's still there, and so pets can reasonably sell at that price. Now imagine, for the sake of argument, if that second user were able to buy a creatu for 100m from an NPC. Then that tu disappears - poof! The cycle ends right there.
The problem is that Rescreatu doesn't have enough of these "poof" opportunities - tu sinks as they are called. NPC shops and the credit shop are really the only major tu sinks I can think of. The credit shop is probably the biggest, but how many people dump tu into that vs cash? The problem is probably exacerbated by the fact that most thing in the credit shop can now only be bought using cash. I also don't count stocks or the springs because the gains from those ultimately negate the losses.
On the other hand, there is a metric crap-ton of tu coming into the economy every day thanks to stocks. Stocks are so low-risk/high-gain it's not even funny. With a single good sell I can pull in upwards of 25-30m tu. If there are 50 other people as lucky as me that day, that's potentially 1.5 billion tu just magically appearing into the economy, in *one* day. And where does it go? likely nowhere. It stays in the economy.
The prices these days are the result of years of this same unchanging economic model. Another problem is that for users who don't know how to use the stocks, their only method of making significant tu is luck of the hatch/name. Pet prices won't go down, because people are able to buy pets at these prices because there is so much tu, but those with the most tu are those who use stocks. So for those who don't use stocks, these prices seem impossibly high.
(I'm a little drunk right now so i hope this was all coherent enough)
I might be talking out my ass a little because I obviously don't have any hard numbers or statistics, but I think the Rescreatu economy has been around long enough and is simple enough to be able to draw such conclusions through observation/induction.
To reiterate, astronomically high prices do not mean we need to introduce more tu into the economy. It means that there's already too much tu, or people wouldn't be able to sell at prices that high. A good long term plan for Rescreatu's economy would probably look something like: nerfing stock gains, introducting more tu sinks (parties plz?), and introducing more varied ways of earning tu.
Also, good pets/items are always going to be hard to get, and that's how it should be.