I've seen/heard people using very small powered combos for small gigs. I would prefer a 100w+ half stack regardless but with a decent sound guy it can sound great.
Either way Devin is talking about Unmiked band practice with a drummer.
Totally agree w/ your points. I am 100% a 100 watt head guy plus 4x12 especially outdoors.
In the 80's i carried a Marsahll stack up 3 flights of stairs by myself.
However those days are over. The combo even tho 50# will create options to the 4x12 heeve ho.