GOG is for people who want to play old games on new hardware. The installers are for newer operating systems (XP to W10). I have purchased a few games from GOG, but don't have a massive library (69 titles) .
I don't mind digital downloads as long as they are super cheap and I get to have the installers in case the company goes bankrupt. Just today I got in the mail from ebay a shrinkwrapped copy of Command and Conquer the Ultimate Collection from EA, 17 games that cost me $12.59 shipped. Assuming the unused key still works I think that is a super deal. Last year (also from ebay) I purchased the Command and Conquer Theater of War pack for cheap (original Command and Conquer, Tiberian Sun, Red Alert 1 and 2 with original CD installers (so you can play on vintage gear 8 CDs total). I still have my original copy of the first few C&C but buying each one now can get pricey.
To be honest most old games can be found using torrents or download sites. Most people who pay crazy money for hardware tend to pirate software (from what I have seen). The people who collect the originals boxed probably don't play them much. I have a bunch of originals purchased over the years, even went crazy buying boxed Amiga and Atari ST games when they were being dumped ages ago.
What I collect: 68K/Early PPC Mac, DOS/Win 3.1 era machines, Amiga/ST, C64/128
Nubus/ISA/VLB/MCA/EISA cards of all types
Boxed apps and games for the above systems
Analog video capture cards/software and complete systems
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