JK,
Why pass on the Aussie model - pull/push trolley with a little sand bucket underneath?
I have only seen those neat little tubes is sand for walkers once, in my limited experience in Nebraska.
At home, I find the 'big mouthed' empty bottles, like Gatorade, are ideal, for filling divots, we play both fescue and couch courses each with divots behaving differently at certain times of the year, and that they often require a top up of sand, to level. And agree with Jon, we replace our fescue divots as they do grow back.
I hope we can implement a walking golfer solution at our club soon, as there is certainly a strong degree of guilt, in Australia anyway, with not carrying sand, especially as a member, and this may encourage more to walk, which is certainly better for the course than cartball.