Kotaku: EA says their loot boxes are "surprise mechanics".

I don't know much about trading cards (I assume you are talking about things like that Magic card playing game and not like baseball cards?), so maybe that is a much more insidious business than I would think it to be.  Who knows?

When we are talking about video game companies, especially current day AAA developers and publishers what I would say sets them apart is their specific targeting of addictive behaviors.  Companies like EA and Activision etc. bringing in experts in areas of psychology and the study of addictive personalities to create content and mechanics specifically designed to exploit that.  Their use of things like digital tracking of player behaviors to learn gamer's patterns and then use that info to then develop content and systems to manipulate those tendencies to maximize the amount of coin they can drain not just from the general population of their consumers but specifically from their "whales".

As a gamer what sets it even further apart for me is the obvious degradation and decline in quality content they produce because all of these games systems and design choices are so transparent in their attempts to funnel people into the cash shops and micro-transactions.  Video games with each year that passes become less and less about providing a quality "video game experience" and more about what kind of shell or recognizable brand do they strap around their cash shop to maximize the profit margin.

Not all games and companies follow that trend obviously, but the overall direction of the industry is definitely away from the "art" of video game making into the realm of being digital casinos.  Which if that is the direction these companies really want to move, more power to them I suppose.  But when they turn their games into digital slot machines they shouldn't be surprised when the powers that be come in and start wanting to regulate and manage them the same way they do other people that run slot machines.