Just because guys can be had for free doesn't mean you'll pick the right ones at the bargin bin basement and if you don't, then you have to go shopping anyway.
Oilers trade a 2 and a 3 for Talbot
Oilers trade a 3 for Scrivens
Oilers trade a 3 and a 5 for Fasth
All those assets to fill out the goaltending position in the last few years for one team.
I always love the Edmonton examples to prove a point.
Dubnyk was garbage there too now somebody is going to pay him 5 million a year.
But the missed point in your example is how easy it is to throw up some low picks and get a goalie...a more developed and known goalie at that...and none of those guys were high picks
Talbot undrafted
Scrivens undrafted
Fasth undrafted
That is how you do it... go sign a goalie out of Europe or the NCAA and trade him not use a #36 overall in a generational draft.
And goalies are moved all the time...Schneider, Rask, Bernier, and Varlomov...there are always goalies available