Price drop on 1st party Nintendo software? Where have you been, breh lol.
Amazon PRIME pre-order or BBGCU are your best medium range bets.
Mario Kart and Zelda dropped over here at amazon.de to 50 and 55 Euro respectively. You can also get ARMS and Splatoon for about 51 Euro incl. shipping from 365games.co.uk too.
Nintendo Games aren't that expensive, at least not the Switch ones, I have yet to experience a higher price than what we've seen with the WiiU(or Xbox One/PS4 for that matter, heck, even Steam, Nier Automata cost me 50 Bucks too for PC and I didn't even get a disc), even though the Switch uses superior cartridge tech over stupid optical media that is prone to scratches and fungi ^^