They *can*. But they *don't*.
While not pushed by quotas, they are tempted by personal incomes directly proportional to in-game sales. Ther is always the incentive to grab more money, whatever it is.
And single-player games can be (and frequently are) made equally hopeless money sinks in pursuit of progress in game, as opposed to advantage over other players. When a game requires you to spend three years to accumulate enough valuables through "free means" to avoid that one $30 payment required to progress (actual example), and this after you've invested about a month of your time to arrive at that point, this is no longer "pay if you want to gain advantage", this is "pay or GTFO."
Once again, this is not about what game companies may do to make these games competetive and fun. This is about the ugly reality of what they actually do, with few very rare exceptions. So, no wonder if a player sees a game announced as F2P, automatically labels it a scam. Because usually it is a scam.