No, buy all games when they get massive price cuts and digital. The only physical games I have are ones I highly anticipate.

I still buy lots of games at launch, especially if I really want them. That said, if I don't get a game launch day, then I will always wait until it's cheaper, even if it only came out a few weeks ago.

I'm 50/50
Most of the games I really want I do get right away so I pay full price. But there are also a number of games that I become interested in later and either get new for a much lower price or a really low used priced.
I wish I wasn't such a sucker for day 1 purchases but I am getting better :D

That's really noble of you.

If I have my eye on a game, I'll usually buy at launch for full MSRP. Too often games and plot points are spoiled by the Internet, and with multiplayer games there's the real chance to miss out on the fun if the products life is cut short (and I absolutely detest/lack faith in the opinion of big review sites like IGN so their scores mean nothing) Ironically ended up buying Overwatch used like two months after launch cuz I wasn't particularily interested in it but the hype. Game is everything it was said to be though, no complaints. Also waited on R6 Siege to hit $24 including season pass on PSN cuz I wasn't sure how different it would be from RS:Vegas. Turns out Siege is the greatest tactical shooter of this gen. 

Only for certain Nintendo games like Zelda, Mario, and Smash. But even then there are many games I'd only consider getting if their prices dropped, like Pokken. Non-Nintendo games I can just wait for a big Steam sale.

Going somewhat off topic, I've heard of this CD-key, but my lack of PC gaming experience hinders me.  Please elaborate.

Due to my budget and free time, games I wish to buy that are released in 2017 will have wait until its cheap. Only if they're limited editions/collectors that I'll buy Day1.

Depends on the game. Some games I just don't have the patience to wait. I have pretty big back log currently so, Horizon will be the only game i'll buy at full price. At least for the first half of this year. Will pick up Nioh, GR 2, and Nier, and ME Andromeda later this year.

I bought like 5 games at launch in my life, I usually wait more than a year before getting them since here they are expensive and don't get price cuts as fast as in NA or other places

Only for the ones I highly anticipate and/or if the preorder bonuses are attractive enough. For instance, I preordered GR2 for the Director's Cut soundtrack and the music is awesome.