They probably don't leak as much as you think. In fact a hose-clamp might actually induce a leak as I doubt that the pressure applied is uniform round. Probably not a problem with softer hoses. The main reason for not having them on though was expense. The initial expense of setting up kegging is huge and hose clamps are almost a buck a piece! and you use 3 per tee plus 2 per keg plus tees costing a few bucks each you start feeling robbed, especially if your thinking that money could just go towards a manifold. I'd go after it with soapy water, but I am tearing that setup down soon to move the kegs indoors for the winter. Plus I just bought a new regulator but have been force carbing kegs for the winter stash for a few weeks straight now, so maybe the leak is gone with the new regulator just haven't around to checking. I've gotten like 5 kegs carbed so far with the needle hovering just above the "order gas" part of the gauge so no major losses.