Same. I bought a cheap set when I began, but I've bought a handful of D6 dice mostly for sneak attacks. Currently, all of my dice can still fit in a 2"×2" cloth drawstring bag.
Why not rolling advantage with two d20 at once? Why playing DnD only? I needed 2d10 to play Ironsworn 10d10 for COPS, 2d6 for Dungeon World, 4d6 for Fate, 10d6 for Shadowrun, ...