The way to decentralise CLAM is for someone to offer a competing service
You are wrong.
Sort of like basketball with one goal 10 feet high and the other one 1000 feet high and saying "we can switch sides when you score basket".
not to artificially limit the biggest source of demand for CLAM.
Every other pool or anything relating to decentralized currency has a moral/crypto obligation in order to "artificially" limit their control over the network to prevent a central point of failure. I remember you before this fucking god complex kicked in and you shared similar beliefs. I even recall you discussing DDoSing Netcodepool or renting mining power to offset them back when they almost crossed the 51% mark early DOGE days.
If I was to stop allowing people to invest in Just-Dice, who do you think would buy the thousands of CLAM that the digger dumps on the market each day?
I think people would buy them and stake them on their own further decentralizing CLAM & encourage other people to dig their CLAMS in order to "open up" more to invest on Just-Dice. They would probably gamble more as well which would be better for investors rather than seeing their investments become more and more diluted. You would also earn more income due to additional play & the network would begin a new life of expanding beyond a central point of failure. (Still accept deposits for gambling, but do not stake the coins.)
It is your site and you are welcome to do what you want, but this type of shit is only flying due to greed.
What would they use them for?
See the answer above. You could actually use this to the investors and your advantage if you'd played your cards right. Open your mind and let people use their CLAMS for whatever they want to use them for. Perhaps the lack of ways to use CLAM would actually encourage the creation of more ways to use CLAMS.
It still blows me away you thought /offsite would do anything

.
Investing in JD accounts for the lion's share of the current demand for CLAM.
It won't be as soon as you actually get serious about decentralization, stop being greedy and do the right thing.