There isn't much weight advantage to saving a couple spokes, but the reverse argument - that *MIGHTY SPRINTERS* manage not to break low spoke wheels - suggests to me that there's no point worrying about it either way.
spokes fail by fatigue; 'the mighty sprinters' won't break the shiny new wheels they are riding that day in the TdF by fatigue. Spokes do break in race bike wheels though; in last year's TdF I think it was a broken spoke that may have contributed to a situation where CF was attacked.
Regarding the whole 'my wheels without many spokes in haven't broken yet, therefore they must all be alright' line of comment: This is a false argument in that something parts can be unacceptably reliable yet nine out of ten users might see no problems in their use. If the part is safety critical even one failure in a hundred is a complete disaster and one every many thousands can be enough to (say) trigger a recall in products like cars.
Wheels work differently depending on how stiff the wheel rim is. The stiffer the rim is, the lower the radial fatigue loading on the spokes is, in an evenly tensioned wheel. However when the wheel is laterally loaded, the fatigue loads on such wheels are still pretty high. So in some uses the expected fatigue life of spokes in low spoke count rims ought to be OK. It very often isn't though for all the usual reasons; bad fit of spokes, bad spokes, bad stress relief, uneven tension in spokes... you name it.
When a spoke does break in such wheels the wheel is liable to go out of true more than a wheel with a greater number of spokes. Worse yet, if you do manage to ride on such a wheel with a broken spoke, the rim often 'takes a set' such that the wheel will never be any good again, i.e. the rim is now bent and the wheel won't be straight and
evenly tensioned, not at the some time anyway.