The GDP grows over time. Yes, we're still dealing with economics based on scarce resources (relatively speaking). That won't change unless we have a technological singularity, and even if that happens, some things of value like land (preferred locations) or esteemed original art pieces will still be scarce commodities.

What's the alternative model? That the government allocates the scarce resources instead of the market? What makes government better at this for most things (allowing for some exceptions)?