Miners do not bring value to bitcoin. In fact miners actually drive the price steadily downward without the influx of new money equaling current market price * 7200 per 24hrs. Since that is very unlikely to continue, we'll just see a steady bleeding of value as miners get desperate and keep selling off coins to cover costs and recoup investment, just as we're seeing. As I said, BTC has been on a slow burn decline ever since Gox opened back up.
Miners are into bitcoin to profit in USD, except the zealots/speculators who hoard, and they're neither hurting nor helping bitcoin.
Bottom line, miners mean jack shit to the value of bitcoin as a "currency" or even a speculative vehicle, since the amount of bitcoins introduced to the market daily remains the same.
It really depends on your POV, classic cup half empty or half full kind of thing. Your assumption is that nothing is going to change so yes, in that situation what you describe could happen.
While I agree it is a likely scenario, it also means ignoring the fact there are people, even as you mentioned some working on a Bitcoin ATM and such, trying to change the landscape and therefore the market. Once somebody puts something out there that is sufficiently attractive paid for by Bitcoins, the economy could get kickstarted properly. For example in your proposed scenario when the value has gone down that miners start selling off to recoup, they may end up spending it within the economy for things that are worth more than the cash they would get, especially after taking into account the charges in getting cash transferred back. In many cases, it just takes that one single change to tip the scales and make what looks like a dog become a star.
Furthermore miners who have no intention of spending originally, may be educated and convinced that by spending some of their hoard in the bitcoin market, they are only helping to drive up the value of their hoard.
Again, no bitcoin economy is coming because bitcoin serves no purpose that other services haven't already filled.
Bitcoin makes a cheap payment processor? So does Dwolla, and there's 75% less bullshit involved.
Bitcoin is a hedge against inflation? No-one gives a shit. There's better stores of value in real tangible assets, like gold.
Bitcoin is secure/anonymous whatever other super-fantastic crypto-bullcrap? Again, no-one in the public gives a shit. There's zero value proposition relative to anything bitcoin is built on.
There's just simply no place in the real people's economy for this little hobby experiment.