Most of us were able to earn money to buy a pizza or some additional snack betting on teams, or trading keys. Some exceptionaly lucky or with natural born trading skills were earning serious money — from quater to multiple salaries of an adult.
Maybe because casino-tourism in Belarus made people here slightly less prone to gambling, or maybe parents were not used to gift their children micro-transactions — e-sports betting, gambling and trading was financed mostly via in-game drops, returns from these bets and trades, and of course, sometimes, pocket money (which, on average were like 3$ per week).
That said, in modern times where micro-transactions are so common that you are ok with giving your kid V-bucks as birthday gift, I want say that anti child gambling narrative is a good thing.
2) At that time, and afaik it is true even today — you could use skins as a virtual currency to pay for a real things. It was proto-cryptocurrency/NFT in terms of being KYC and AML free.
This is really big market. There are aritcles on NYT about real life terrorists buying real guns for skins.
But without US-centric sensationalism, I beleive you can still pay for VPN or ChatGPT in very sanctioned Russia in CS skins. This can be also done with crypto (and mostly done now), but crypto has learning curve and you already playing CS.