I expect the game to have great legs, so the first three days are not telling the whole story. Add to that the higher price and a larger share of digital sales and I'm sure Let's Go is making a lot of money.
Still, the whole "attach rate" comparison seems to be slightly flawed to say the least...
Anyways, fantastic hardware numbers.
Attach rate % is a better comparison then just raw 3 day sales. Either way trying to compare the lgp/e sales to other pokemon games is tough when lgp/e are more expensive games on more expensive hardware. I don't recall people crying bomba for Monster Hunter World when it sold half the number week one compared to Monster Hunter 4 and the other 3ds MH titles (I'm sure some did but that's besides the point).