Amid the mainland's round of reforms in the financial system, Beamish expects China will open its capital account more quickly than many are currently anticipating.
"Illicit flows out of China will be liberalized," she said. "That particular demand for going to the casino may be diminished."
Beamish is also skeptical of China's much-touted shift toward consumer-led growth from an investment-led economy.
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"It won't necessarily happen in a successful way," she said. "Investment is very weak and private consumption is by default the strongest thing in the economy," she added, noting she expects economic growth may slow to around 5 percent this year as well as in years ahead, compared with an official target of around 7.5 percent.
"You're going to have a similar amount, or less, of private consumption, but private consumption is leading growth," she said.
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Of course, frontier casino markets may be able to profit even if the hoped-for Chinese tourists don't materialize.
Gaming in Asia is underpenetrated, Macquarie said in a report in December, citing a growing number of high-net-worth individuals and a growing acceptance of integrated casino resorts as a form of entertainment.
For example, it believes the Philippines' domestic market is also promising and its forecast for gaming growth there may be more bullish than Citigroup's; Macquarie forecasts the gaming market may grow to $4.8 billion by 2017.
"Not only is the Philippines seeing strong economic growth, but the demographics are also supportive of higher disposable incomes and greater growth in consumption expenditure," it said, although it noted competition in the market is intense.
—By CNBC.Com's Leslie Shaffer; Follow her on Twitter