Er, also allowing them to grow infinitely. Note that they will only grow infinitely as long as people are trading them for MORE than the cost of production. It seems to me at some point people would say "OK, it seems like our economy is big enough to do our business now", and the demand price would drop below cost of production. At this point people would stop generating them, because there is no-one to sell them to for profit (and even if they wanted to speculate, they would could just buy them for less).
It seems to me perfectly fine to let them grow infinitely, and in fact this will not cause the value of existing coins to decrease, because it cost money/resources to produce the new coin
. Much like when a VC meets with a corporation and gives a pre-money valuation
of $1 million for their existing 500 shares. The corporation then creates 500 new shares and sells them to the VC at $1 million, meaning there are now 1000 shares. But the existing 500 shares are worth exactly the same amount as they were before, because the company now has a of $2 million.