What people seem to miss about this game is that it is truly a game for enthusiasts and/or collectors. A lot of people would like to drive trains, but not everyone can afford to buy a train. Thus, they can buy this game which is as close as you're going to get without actually driving a real train.
The sheer amount of DLC is simply there for collectors. If you're interested in a particular type of train, you buy that DLC. Those you are not interested in, you don't buy. The majority of the DLC isn't even made by the original devs either. It's made by independent creators who then sell it for the game, with a sum of the proceeds going to the original developers. That's also why the DLC is generally so expensive, as they cater for a niche market, a large part of which might not be interested in the particular train you're selling. You can't sell 100s of hours of development time for $5 in a market where maybe 200 - 500 people will buy your DLC.
Either way, train simulation games do not fall within my interests, but I thought I'd just clarify as I've spoken to a few people who are interested in these games and I feel this game gets an unnecessary amount of flak from people who simply don't understand the concept and lure of it.
