Never, why should I be embarrassed to play some of my most liked games? I can just as easily play a round of DOTA or Starcraft in front of my friends and then play Pokemon or Mario in front of them as well.
Your whole assumption is that Nintendo games = kids games, which is far from the truth. Nintendo games are for every age and for every gamer. Or at least, every gamer that has the ability to see and comprehend anything beyond the limited current view of "OMGZ I IZ THE HARDCOREZ".
Current PC Build
CPU - i7 8700K 3.7 GHz (4.7 GHz turbo) 6 cores OC'd to 5.2 GHz with Watercooling (Hydro Series H110i) | MB - Gigabyte Z370 HD3P ATX | Gigabyte GTX 1080ti Gaming OC BLACK 11G (1657 MHz Boost Core / 11010 MHz Memory) | RAM - Corsair DIMM 32GB DDR4, 2400 MHz | PSU - Corsair CX650M (80+ Bronze) 650W | Audio - Asus Essence STX II 7.1 | Monitor - Samsung U28E590D 4K UHD, Freesync, 1 ms, 60 Hz, 28"
