Obviously, yes.
And the wallet owner has to be well-known+trustworthy.
But apart from that, it might work. Maybe even better than standard donations or even crowd-funding websites such as kickstarter. Hell, you could even combine them all!
Well at least for a "community-driven game" it would make sense.
Ya I think this would have been fine if they just said they were going to, allowed people to opt in and stated what the money would be used for (namely prizes of course)