vayne sustain damage

so i was thinking about vayne and why people play her with a weird build and domination secondary runes with press the atack or the past runes and items that i have already tried but in my opinion they dont know how to play vayne they are actually building wrong items and runes https://www.youtube.com/watch?v=JhqeZbHCGsI&feature=youtu.be when you can actually deal a lot more damage if they build vayne like the old days build like i cant understand why people do that? seriously they are playing like pros build runes even if they are wrong and honestly all of the runes they pick are wrong everytime wrong keystone at first runes option then wrong secondary runes can you explain me why they take domination on vayne? or biscuits with free boot when they can get a high amount of damage from sorcery and from adaptive force?and actually build like old style vayne?personally i have tried a lot of diferent playstyles with vayne and honestly all playstyles of pros are so stupid and actually deals no damage and 0 sustain damage or healing.