I think that if blame should be placed anywhere, it should be on developers rather than consumers. Developers are the ones who need to make a living off their work, but they are very very good at devaluing their work. Developers, by and large, are spectacularly bad at anything business or marketing related. They’re often vicious and will turn on other developers who are trying to make money, complaining and demanding things to be cheap or free. Other than setting up the marketplace, has Apple actually done much to drive prices down, or have developers done it all themselves? The free upgrade model is reprehensible, but things like family sharing are opt-in and pricing isn’t mandated anywhere.
But of course, things are more complicated than that. The distribution of developers is skewed towards young, naive people with few obligations and low expectations. They probably put their apps on sale for $1.99 without sparing a thought for the sustainability of their pricing model. These are also people who are able to develop apps on the side, in addition to being employed, so if they get an extra few hundred dollars a month, they think it’s a nice bonus. Income disparity also likely plays a role in a globalised marketplace like this.
From yet another angle, this is exactly what capitalism is supposed to do: drive prices down, the fates of labour be damned. It’ll all be for the best in the end, right? Well, it won’t. The end game is cheap shit and products rolling out of giant corporations that sprout unsavoury externalities all over the place.