The risk is for sure, I can't argue that.
I would argue that the 'point' is anonymity -- there are many points to BTC. Deflationary, unregulated, international are three off of the top of my head.
And we do group buys with BTC all the time.
Much like here, they require a champion (someone who collects the money), transparency (which the blockchain allows beyond the 'goodness' of the champion, by broadcasting all transactions. It shows exactly who sent what, how much and where, readily available to everyone -- including transaction signatures). And finally, the vendor simply needs to be registered with BitPay (minimal fees, less than PayPal or comparable servies), which immediately converts BTC into fiat of choice (USD, for instance) at the time of transaction.
Of course, the last point requires the vendor to accept BTC.. which goes back to my original question